dr hab. inż. Piotr Kiełczyński 

Doktorat
1979  Propagacja poprzecznych fal powierzchniowych w ośrodkach sprężystych o zmiennych własnościach fizycznych
 323 
Habilitacja
2000  Pola akustyczne przetworników i układów ultradźwiękowych o niejednorodnym rozkładzie amplitudy drgań na powierzchni 
Ostatnie publikacje
1.  Kiełczyński P., Direct Sturm–Liouville problem for surface Love waves propagating in layered viscoelastic waveguides, Applied Mathematical Modelling, ISSN: 0307904X, DOI: 10.1016/j.apm.2017.09.013, Vol.53, pp.419432, 2018 Streszczenie: This paper presents theoretical model for shearhorizontal (SH) surface acoustic waves of the Love type propagating in lossy waveguides consisting of a lossy viscoelastic layer de posited on a lossless elastic halfspace. To this end, a direct Sturm–Liouville problem that describes Love waves propagation in the considered viscoelastic waveguides was formu lated and solved, what constitutes a novel approach to the stateoftheart. To facilitate the solution of the complex dispersion equation, the Author employed an original ap proach that relies on the separation of its real and imaginary part. By separating the real and imaginary parts of the resulting complex dispersion equation for a complex wave vec tor k = k 0 + j αof the Love wave, a system of two real nonlinear transcendental algebraic equations for k 0 and αhas been derived. The resulting set of two algebraic transcenden tal equations was then solved numerically. Phase velocity v p and coefficient of attenuation αwere calculated as a function of the wave frequency f , thickness of the surface layer h and its viscosity η44 . Dispersion curves for Love waves propagating in lossy waveguides, with a lossy surface layer deposited on a lossless substrate, were compared to those cor responding to Love surface waves propagating in lossless waveguides, i.e., with a lossless surface layer deposited on a lossless substrate. The results obtained in this paper are orig inal and to some extent unexpected. Namely, it was found that: 1) the phase velocity v p of Love surface waves increases as a function of viscosity η44 of the lossy surface layer, and 2) the coefficient of attenuation αhas a maximum as a function of thickness h of the lossy surface layer. The results obtained in this paper are novel and can be applied in geo physics, seismology and in the optimal design and development of viscosity sensors, bio and chemosensors. Słowa kluczowe: Sturm–Liouville problem; Complex dispersion equation; Surface acoustic love waves; Eigenvalues; Elastic waves; Viscoelastic waveguides Afiliacje autorów:
 35p.  
2.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Rostocki A.^{♦}, Ptasznik S.^{♦}, Evaluation of HighPressure Thermophysical Parameters of the Diacylglycerol (DAG) Oil Using Ultrasonic Waves, Food and Bioprocess Technology, ISSN: 19355130, DOI: 10.1007/s1194701618276, Vol.10, No.2, pp.358369, 2017 Streszczenie: Modeling of highpressure technological processes in the food industry requires knowledge of thermophysical parameters of processed foodstuffs in a broad range of pressures and temperatures. However, the highpressure thermophysical parameters of foodstuffs are very rarely published in the literature. Therefore, further research is necessary to achieve a deeper insight into the biophysical and thermophysical phenomena under pressure to provide better control of technological processes and optimize the effects of pressure. The essential goal of this work is to evaluate the impact of high pressure and temperature on the thermophysical parameters of liquid foodstuffs on the example of diacylglycerol (DAG) oil (which attracted recently a considerable attention from research and industrial communities due to its remarkable benefits for health), using ultrasonic wave velocity and density measurements. Isotherms of adiabatic and isothermal compressibility, isobaric thermal expansion coefficient, internal pressure, and thermal pressure coefficient versus pressure were evaluated, based on the measurement of the compressional ultrasonic wave velocity and density of DAG oil at high pressures (up to 500 MPa) and at various temperatures. The adiabatic compressibility is affected mostly by the changes of pressure, i.e., it grows about four times when the pressure increases from the atmospheric pressure (0.1 MPa) to 400 MPa at a temperature of 50 °C. By contrast, the internal pressure is a pronounced function of the temperature, i.e., it increases six times when the temperature rises from 20 to 50 °C at a pressure of a 200 MPa. To perform numerical calculations, it was convenient to introduce a Tammann–Tait type equation of state to approximate the measured density isotherms of the investigated DAG oil. The results obtained in this paper can be applied in modeling and optimization of highpressure technological processes and processing of foodstuffs. Evaluation of highpressure isotherms of the considered thermophysical parameters of the DAG oil is an original authors’ contribution to the stateoftheart. Słowa kluczowe: Highpressure food processing, Diacylglycerols, Thermophysical parameters, Isothermal compressibility, Isobaric thermal expansion coefficient, Ultrasonic methods Afiliacje autorów:
 35p.  
3.  Kiełczyński P., Ptasznik S.^{♦}, Szalewski M., Balcerzak A., Wieja K., Rostocki A.J.^{♦}, Thermophysical properties of rapeseed oil methyl esters (RME) at high pressures and various temperatures evaluated by ultrasonic methods, Biomass and Bioenergy, ISSN: 09619534, DOI: 10.1016/j.biombioe.2017.09.015, Vol.107, pp.113121, 2017 Streszczenie: Investigation of the highpressure thermophysical properties of biofuels, e.g., bulk modulus, Surface tension, and viscosity is of paramount importance in fuel injection systems in diesel engines. Another crucial and dangerous phenomenon that may occur in biofuels at high pressures is phase transition (solidification), which can drastically increase the viscosity of the biofuel. This effect may hamper proper operation of the engine, especially under coldstart conditions. Unfortunately, the availability of highpressure thermophysical properties of biofuels is still limited. The goal of this paper is to investigate the impact of high pressures on thermophysical properties of biofuels on the example of rapeseed fatty acid methyl esters (RME) in a wide range of pressures (0:1 to 250 MPa) and temperatures (5 to 20 _C). To this end we employed innovative ultrasonic techniques, i.e., the BleusteinGulyaev surface acoustic waves for measuring RME viscosity, and ultrasonic bulk compressional waves for measuring sound velocity in RME and consequently evaluating RME thermophysical parameters, e.g., bulk modulus and surface tension. The viscosity of the measured RME displayed an abrupt increase at pressures: 260 MPa (t Ľ 20 _C), 230 MPa (t Ľ 15 _C), 190 MPa (t Ľ 10 _C), and 130 MPa (t Ľ 5 _C). Evidently it was a signature of the phase transition (solidification) occurring in the RME. The discovered high viscosity highpressure phase in RME can be very detrimental for operation of modern common rail Diesel engines. Therefore, the results of research presented in this paper should be interesting for engineers and designers working with modern common rail Diesel engines using biofuels. Słowa kluczowe: Biofuels; Methyl esters; Phase transitions; Viscosity; Speed of sound; Ultrasonic methods; High pressure Afiliacje autorów:
 35p.  
4.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Propagation of ultrasonic Love waves in nonhomogeneous elastic functionally graded materials, Ultrasonics, ISSN: 0041624X, DOI: 10.1016/j.ultras.2015.10.001, Vol.65, pp.220227, 2016 Streszczenie: This paper presents a theoretical study of the propagation behavior of ultrasonic Love waves in nonhomogeneous functionally graded elastic materials, which is a vital problem in the mechanics of solids. The elastic properties (shear modulus) of a semiinfinite elastic halfspace vary monotonically with the depth (distance from the surface of the material). The Direct Sturm–Liouville Problem that describes the propagation of Love waves in nonhomogeneous elastic functionally graded materials is formulated and solved by using two methods: i.e., (1) Finite Difference Method, and (2) HaskellThompson Transfer Matrix Method. Słowa kluczowe: Ultrasonic Love waves, Functionally graded materials, Profiles of elastic constants, Direct Sturm–Liouville Problem, Group velocity Afiliacje autorów:
 30p.  
5.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Inverse Method for Determining Profiles of Elastic Parameters in the Functionally Graded Materials using Love Waves, ACTA ACUSTICA UNITED WITH ACUSTICA, ISSN: 16101928, DOI: 10.3813/AAA.918961, Vol.102, pp.428435, 2016 Streszczenie: This paper presents the use of SH (Shear Horizontal) surface Love waves to determine the distributions of elastic parameters in nonhomogeneous Functionally Graded Materials. The advantage of Love waves applied to investigate the elastic properties of materials is that the Love wave energy (in contrast to the other types of waves, e.g., plate Lamb waves) is concentrated in the vicinity of the surface layer. The penetration depth of the SH surface Love waves depends on the frequency. Therefore, Love waves are particularly suitable for investigating the profiles of the mechanical properties in nonhomogeneous Graded Materials. Direct Problem (Direct SturmLiouville Problem) that describes the propagation of Love waves in nonhomogeneous graded materials has been formulated and solved numerically by applying the Transfer Matrix Method. The Inverse Procedure (Inverse SturmLiouville Problem) for determining the distribution of elastic properties versus depth in the nonhomogeneous materials has been developed. Love wave dispersion curves in nonhomogeneous graded materials were evaluated numerically (synthetic data). Using the evaluated dispersion curves of Love waves and a developed Inverse Procedure the distributions of elastic shear coefficient as a function of depth (distance from the surface of the material into the bulk) in a heterogeneous surface layer deposited on a homogeneous substrate have been evaluated. Power type profiles (i.e., root square, linear and quadratic) of the shear elastic coefficient in the surface layer were considered. The results of this study can be useful in the investigation of elastic properties of Graded Materials in electronics as well as in geophysics and seismology. Słowa kluczowe: Love waves, Inverse Methods, Functionally Graded Materials, Elastic parameters, SturmLiouville Problem Afiliacje autorów:
 25p.  
6.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Rostocki A.J.^{♦}, Siegoczyński R.M.^{♦}, Ultrasonic Evaluation of Thermodynamic Parameters of Liquids Under High Pressure, IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL, ISSN: 08853010, DOI: 10.1109/TUFFC.2015.007053, Vol.62, No.6, pp.11221131, 2015 Streszczenie: In many technological processes (e.g., in the chemical, petrochemical, food, and plastics industries), liquids are subjected to high pressures and temperatures. Therefore, knowledge of their thermodynamic properties is essential for understanding, design, and control of the process technology. Direct evaluation of the thermodynamic parameters of liquids under high pressure, using conventional methods, is very difficult. Therefore, the application of these methods in industrial conditions, particularly in online control of the technological parameters of liquids, is practically impossible. Ultrasonic methods (e.g., sound speed measurements) are very suitable for this purpose because of their simplicity and accuracy. The sound velocity is closely related to numerous thermodynamic properties of liquids. The objective of this paper is to address the influence of temperature and pressure on the thermodynamic parameters of liquids, using the example of diacylglycerol (DAG) oil, employing ultrasonic methods. In this paper, we present ultrasonic velocity and density measurements (performed by the authors) in DAG oil over a range of pressures and temperatures. On the basis of experimental results (the sound velocity and liquid density versus pressure and temperature) a series of DAG oil thermodynamic parameters such as specific heat ratio, intermolecular free path length, Van der Waals constant b, surface tension, and effective Debye temperature were evaluated as functions of pressure and temperature. Słowa kluczowe: Thermodynamical properties of liquid, High pressure food processing, ultrasonic methods, sound velocity, surface tension Afiliacje autorów:
 30p.  
7.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Group and Phase Velocity of Love Waves Propagating in Elastic Functionally Graded Materials, ARCHIVES OF ACOUSTICS, ISSN: 01375075, DOI: 10.1515/aoa20150030, Vol.40, No.2, pp.273281, 2015 Streszczenie: This paper presents a theoretical study of the propagation behaviour of surface Love waves in nonhomogeneous functionally graded elastic materials, which is a vital problem in acoustics. The elastic properties (shear modulus) of a semiinfinite elastic halfspace vary monotonically with the depth (distance from the surface of the material). Two Love wave waveguide structures are analyzed: 1) a nonhomogeneous elastic surface layer deposited on a homogeneous elastic substrate, and 2) a semiinfinite nonhomogeneous elastic halfspace. The Direct SturmLiouville Problem that describes the propagation of Love waves in nonhomogeneous elastic functionally graded materials is formulated and solved 1) analytically in the case of the step profile, exponential profile and 1cosh2 type profile, and 2) numerically in the case of the power type profiles (i.e. linear and quadratic), by using two numerical methods: i.e. a) Finite Difference Method, and b) HaskellThompson Transfer Matrix Method. Słowa kluczowe: surface Love waves, group velocity, phase velocity, functionally graded materials, profiles of elastic constants, direct SturmLiouville problem Afiliacje autorów:
 15p.  
8.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Rostocki A.J.^{♦}, Siegoczyński R.M.^{♦}, Ptasznik S.^{♦}, Application of ultrasonic wave celerity measurement for evaluation of physicochemical properties of olive oil at high pressure and various temperatures, LWTFOOD SCIENCE AND TECHNOLOGY, ISSN: 00236438, DOI: 10.1016/j.lwt.2014.01.027, Vol.57, pp.253259, 2014 Streszczenie: Highpressure processing is a powerful technology for food preservation. The knowledge of foods properties in the highpressure range is important to develop and optimize such processes by means of mathematical modeling and simulation. Ultrasonic methods are rapid, noninvasive and can be used to characterize foods like edible oils (e.g., composition, purity, and quality assessment). In this paper, they were applied for the investigation of physicochemical properties of olive oil at high pressure at different temperatures. The sound wave velocity was measured by the pulsetransmission method and the corresponding oil density was additionally determined from the monitoring of sample volume change. Measurements were conducted in the pressure range up to 600 MPa, for temperatures from 20 to 50°C. Intermolecular free length, isothermal and adiabatic compressibility versus pressure were calculated using measured sound speed and density isotherms. Discontinuities in the measured isotherms of sound speed and density versus pressure indicate the presence of liquidtosolid phase transitions. The kinetics of the liquidtosolid phase transition was also investigated. The transformation times of olive oil augment with increasing temperature. This study can be broadened to other liquid foodstuffs to investigate the influence of temperature on their physicochemical properties at high pressure. Słowa kluczowe: Physicochemical properties, Intermolecular free length, Ultrasonic velocity, Highpressure food processing, Olive oils Afiliacje autorów:
 35p.  
9.  Kiełczyński P., Szalewski M., Balcerzak A., Inverse procedure for simultaneous evaluation of viscosity and density of Newtonian liquids from dispersion curves of Love waves, JOURNAL OF APPLIED PHYSICS, ISSN: 00218979, DOI: 10.1063/1.4891018, Vol.116, pp.04490217, 2014 Streszczenie: Simultaneous determination of the viscosity and density of liquids is of great importance in the monitoring of technological processes in the chemical, petroleum, and pharmaceutical industry, as well as in geophysics. In this paper, the authors present the application of Love waves for simultaneous inverse determination of the viscosity and density of liquids. The inversion procedure is based on measurements of the dispersion curves of phase velocity and attenuation of ultrasonic Love waves. The direct problem of the Love wave propagation in a layered waveguide covered by a viscous liquid was formulated and solved. Love waves propagate in an elastic layered waveguide covered on its surface with a viscous (Newtonian) liquid. The inverse problem is formulated as an optimization problem with appropriately constructed objective function that depends on the material properties of an elastic waveguide of the Love wave, material parameters of a liquid (i.e., viscosity and density), and the experimental data. The results of numerical calculations show that Love waves can be efficiently applied to determine simultaneously the physical properties of liquids (i.e., viscosity and density). Sensors based on this method can be very attractive for industrial applications to monitor online the parameters (density and viscosity) of process liquid during the course of technological processes, e.g., in polymer industry. Słowa kluczowe: Viscosity, Inverse problems, Wave attenuation, Mechanical waves, Viscosity measurements Afiliacje autorów:
 30p.  
10.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Malanowski A.^{♦}, Kościesza R.^{♦}, Tarakowski R.^{♦}, Rostocki A.J.^{♦}, Siegoczyński R.M.^{♦}, Determination of physicochemical properties of diacylglycerol oil at high pressure by means of ultrasonic methods, Ultrasonics, ISSN: 0041624X, DOI: 10.1016/j.ultras.2014.06.013, Vol.54, No.8, pp.21342140, 2014 Streszczenie: The purpose of the paper is to address, using ultrasonic methods, the impact of temperature and pressure on the physicochemical properties of liquids on the example of diacylglycerol (DAG) oil. The paper presents measurements of sound velocity, density and volume of DAG oil sample in the pressure range from atmospheric pressure up to 0.6 GPa and at temperatures ranging from 20 to 50°C. Słowa kluczowe: Ultrasonic methods, Sound velocity, Phase transitions, High pressure food processing, Physicochemical parameters Afiliacje autorów:
 30p.  
11.  Kiełczyński P., Szalewski M., Transistor Effect in the Cochlear Amplifier, ARCHIVES OF ACOUSTICS, ISSN: 01375075, DOI: 10.2478/aoa20140012, Vol.39, No.1, pp.117124, 2014 Streszczenie: The paper presents a new electromechanical amplifying device i.e., an electromechanical biological transistor. This device is located in the outer hair cell (OHC), and constitutes a part of the Cochlear amplifier. The physical principle of operation of this new amplifying device is based on the phenomenon of forward mechanoelectrical transduction that occurs in the OHC's stereocilia. Operation of this device is similar to that of classical electronic Field Effect Transistor (FET). In the considered electromechanical transistor the input signal is a mechanical (acoustic) signal. Whereas the output signal is an electric signal. It has been shown that the proposed electromechanical transistor can play a role of the active electromechanical controlled element that has the ability to amplify the power of input AC signals. The power required to amplify the input signals is extracted from a battery of DC voltage. In the considered electromechanical transistor, that operates in the amplifier circuit, mechanical input signal controls the flow of electric energy in the output circuit, from a battery of DC voltage to the load resistance. Small signal equivalent electrical circuit of the electromechanical transistor is developed. Numerical values of the electrical parameters of the equivalent circuit were evaluated. The range, which covers the levels of input signals (force and velocity) and output signals (voltage, current) was determined. The obtained data are consistent with physiological data. Exemplary numerical values of currents, voltages, forces, vibrational velocities and power gain (for the assumed input power levels below 1 picowatt (1012 W)), were given. This new electromechanical active device (transistor) can be responsible for power amplification in the cochlear amplifier in the inner ear. Słowa kluczowe: cochlear amplifier, acoustoelectric transducers, electromechanical transistor, equivalent circuits, field effect transistors, ion currents Afiliacje autorów:
 15p.  
12.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Rostocki A.J.^{♦}, Siegoczyński R.M.^{♦}, Thermodynamic Method for Measuring the B/A Nonlinear Parameter Under High Pressure, ENGINEERING TRANSACTIONS (ROZPRAWY INŻYNIERSKIE), ISSN: 0867888X, Vol.62, No.1, pp.515, 2014 Streszczenie: The nonlinearity parameter B/A is a measure of the nonlinearity of the equation of state for a fluid. The nonlinearity parameter B/A is a physical parameter often used in acoustics, from underwater acoustics to biology and medicine. It can provide information about structural properties of the medium, internal pressure and intermolecular spacing. The thermodynamic method has been applied for determination of B/A parameter in diacylglycerol (DAG) oil as a function of pressure at various temperatures. Isotherms of the density and phase velocity of longitudinal ultrasonic wave as a function of pressure have been measured. Using the thermo dynamic method along with measured isotherms of sound speed and density, the nonlinearity parameter B/A (for DAG oil) was evaluated as a function of pressure (up to 220 MPa) at various temperatures ranging from 20 to 50◦C. Słowa kluczowe: Nonlinearity parameter B/A, thermodynamic method, high pressure, longitudinal ultrasonic wave velocity Afiliacje autorów:
 7p.  
13.  Rostocki A.J.^{♦}, Tarakowski R.^{♦}, Kiełczyński P., Szalewski M., Balcerzak A., Ptasznik S.^{♦}, The Ultrasonic Investigation of Phase Transition in Olive Oil up to 0,7 GPa, JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY, ISSN: 0003021X, DOI: 10.1007/s1174601322232, Vol.90, No.6, pp.813818, 2013 Streszczenie: This paper presents measurements of sound velocity and attenuation in olive oil, with known chemical composition, as a function of pressure, within the range of pressure up to 0.7 GPa. Dependencies of sound velocity, relative ultrasonic wave attenuation, volume, and adiabatic compressibility on pressure show discontinuities. This proves the existence of the first order phase transition in olive oil (liquid to solidlike phase transition). Rapid and large changes in relative attenuation testify to the existence of a phase transition in olive oil. Moreover, the kinetics of phase transition was also investigated. Measurement of acoustic wave velocity and relative attenuation in olive oil during the phase transition and in the highpressure phase is a novelty. The results obtained can be useful in the development of new methods in food (edible oils) control, processing, and preservation. Słowa kluczowe: Vegetable oils, Sound velocity, Triacylglycerols, Phase transition, High pressure Afiliacje autorów:
 30p.  
14.  Rostocki A.J.^{♦}, Malanowski A.^{♦}, Tarakowski R.^{♦}, Szlachta K.^{♦}, Kiełczyński P., Szalewski M., Balcerzak A., Ptasznik S.^{♦}, The sound velocity measurement in diacylglycerol oil under high pressure, HIGH PRESSURE RESEARCH, ISSN: 08957959, DOI: 10.1080/08957959.2013.769975, Vol.33, No.1, pp.172177, 2013 Streszczenie: In this article, the influence of high pressure on sound velocity at 293 K has been presented. The investigated diacylglycerol oil (DAG – [D82T18]AG) was composed of 82% DAGs and 18% triacylglycerols. The variation of sound velocity with hydrostatic pressure for DAG was evaluated up to 400 MPa. The phase transformation in DAG has been observed as a discontinuity of the dependence of sound velocity on pressure. The sound velocity during the phase transition has shown distinct increment. Also the volume changes have been measured. It has shown the rapid drop of the volume at the phase transformation pressure due to the possible crystallization of DAG oil. Słowa kluczowe: high pressure, velocity, DAG Afiliacje autorów:
 25p.  
15.  Malanowski A.^{♦}, Rostocki A.J.^{♦}, Kiełczyński P., Szalewski M., Balcerzak A., Kościesza R.^{♦}, Tarakowski R.^{♦}, Ptasznik S.^{♦}, Siegoczyński R.M.^{♦}, Viscosity and compressibility of diacylglycerol under high pressure, HIGH PRESSURE RESEARCH, ISSN: 08957959, DOI: 10.1080/08957959.2013.775649, Vol.33, No.1, pp.178183, 2013 Streszczenie: The influence of high pressure on viscosity and compressibility of diacylglycerol (DAG) oil has been presented in this paper. The investigated DAG oil was composed of 82% of DAGs and 18% TAGs (triacylglycerols). The dynamic viscosity of DAG was investigated as a function of the pressure up to 400 MPa. The viscosity was measured by means of the surface acoustic wave method, where the acoustic waveguides were used as sensing elements. As the pressure was rising, the larger ultrasonic wave attenuation was observed, whereas amplitude decreased with the liquid viscosity augmentation. Measured changes of physical properties were most significant in the pressure range near the phase transition. Deeper understanding of DAG viscosity and compressibility changes versus pressure could shed more light on thermodynamic properties of edible oils. Słowa kluczowe: DAG viscosity, compressibility, phase transitions, transmitted and scattered light Afiliacje autorów:
 25p.  
16.  Kiełczyński P., Power Amplification and Selectivity in the Cochlear Amplifier, ARCHIVES OF ACOUSTICS, ISSN: 01375075, DOI: 10.2478/aoa20130010, Vol.38, No.1, pp.8392, 2013 Streszczenie: This paper presents a new model that describes the physical phenomena occurring in an individual Outer Hair Cell (OHC) in the human hearing organ (Cochlea). The new model employs the concept of parametric amplification and piezoelectricity. As a consequence, the proposed model may explain in a natural way many as yet unresolved problems about the mechanisms of: 1) power amplification, 2) nonlinearity, 3) fine tuning, or 4) high sensitivity that take place in the human hearing organ. Mathematical analysis of the model is performed. The equivalent electrical circuits of an individual OHC are established. The high selectivity of the OHC parametric amplifier is analyzed by solving the resulting Mathieu and Ince differential equations. An analytical formula for the power gain in the OHC’s parametric amplifier has been developed. The proposed model has direct physical interpretation and all its elements have their physical counterparts in the actual structure of the cochlea. The numerical values of the individual elements of the electrical equivalent circuits are consistent with the experimental physiological data. It is anticipated that the proposed new model may contribute in future improvements of human cochlear implants as well as in development of new digital audio standards. Słowa kluczowe: piezoelectricity, parametric amplification, mechanism of hearing, electroacoustic transducers Afiliacje autorów:
 20p.  
17.  Piekarski S., Kiełczyński P., Szalewski M., Rewekant M.^{♦}, Computerbased simulation of plasma concentration timeprofiles of drug in nonlinear twocompartment model, COMPUTER ASSISTED METHODS IN ENGINEERING AND SCIENCE, ISSN: 22993649, Vol.20, pp.279288, 2013 Streszczenie: The main interest of pharmacokinetics is the study of the fate of drugs in the living organism. This work proposes the system of the conservation laws that describes timedependent concentrations of a drug, after a single intravenous administration. Compared with others, the proposed model considers both free and proteinbound drug concentrations at the same time. Plasma protein binding captured in the model enters the nonlinearity arising from the GuldbergWaage law. According to our best knowledge, the analytical solution for our system does not exist. Our model allows the calculation of the free and bounddrug protein concentrations at any time point and at any dose after single intravenous bolus dose administration. In order to compare the empirical with simulated data, a numerical approach has been proposed. On the basis of published experimental data the model validation has been carried out. The goodness of fit was satisfactory (R2 = 0.99) and the experimental and simulated AUC (area under the curve) values, as the measure of the bioavailability of drug, were similar (150 M/hxh−1). The preliminary assessment of the model credibility was positive and encouraged further studies. Słowa kluczowe: Evolution equations, nonlinear model, drug protein binding Afiliacje autorów:
 4p.  
18.  Kiełczyński P., Szalewski M., Balcerzak A., Malanowski A.^{♦}, Siegoczyński R.M.^{♦}, Ptasznik S.^{♦}, Investigation of highpressure phase transitions in DAG (diacylglycerol) oil using the Bleustein–Gulyaev ultrasonic wave method, FOOD RESEARCH INTERNATIONAL, ISSN: 09639969, DOI: 10.1016/j.foodres.2012.07.025, Vol.49, pp.6064, 2012 Streszczenie: In this paper, phase transitions in diacylglycerol (DAG) oil are investigated by using an ultrasonic method for measuring viscosity. Viscosity of diacylglycerol (DAG) oil is measured over a wide range of hydrostatic pressures up to 500 MPa, and at temperatures ranging from 10 to 40 °C. The observed discontinuities in the viscosity versus pressure curves (isotherms) indicate phase transitions. An original ultrasonic method that uses the surface acoustic Bleustein–Gulyaev (B–G) wave was employed to measure the viscosity of DAG oil at high pressure range. This method allows for fast and reliable measurement of DAG oil viscosity along various isotherms. Moreover, the kinetics of the observed phase transformations at various temperatures was analyzed. The results of the study are a novelty, and can be helpful in evaluating the physicochemical properties of edible oils. Słowa kluczowe: Edible oils, Ultrasonic methods, Diacylglycerols, Viscosity, Phase transitions, High pressure Afiliacje autorów:
 40p.  
19.  Kiełczyński P., Szalewski M., Balcerzak A., Effect of a viscous liquid loading on Love wave propagation, INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES, ISSN: 00207683, DOI: 10.1016/j.ijsolstr.2012.04.030, Vol.49, No.17, pp.23142319, 2012 Streszczenie: This paper describes a theory of surface Love waves propagating in a layered elastic waveguide loaded on its surface by a viscous (Newtonian) liquid. An analytical expression for the complex dispersion equation of Love waves has been established. The real and imaginary parts of the complex dispersion equation were separated and resulting system of nonlinear algebraic equations was solved numerically. The influence of the viscosity of liquid on the dispersion curves of phase velocity, the wave attenuation and the distribution of the Love wave amplitude is analyzed numerically. The propagation loss is produced only by the viscosity of liquids. Elastic layered waveguide is assumed to be lossless. The numerical solutions show the dependence of the phase velocity change, the wave attenuation and the wave amplitude distribution in terms of the liquid viscosity and the wave frequency. The results of the investigations are fundamental and can be applied in the design and development of liquid viscosity sensors and biosensors, in NonDestructive Testing (NDT) of materials, in geophysics and seismology. Słowa kluczowe: Love waves, Viscous liquids, Dispersion relations, Attenuation, Viscosity sensors Afiliacje autorów:
 40p.  
20.  Rostocki A.J.^{♦}, Siegoczyński R.M.^{♦}, Kiełczyński P., Szalewski M., Balcerzak A., Zduniak M.^{♦}, Employment of a novel ultrasonic method to investigate high pressure phase transitions in oleic acid, HIGH PRESSURE RESEARCH, ISSN: 08957959, Vol.31, No.2, pp.334338, 2011 Streszczenie: In this work, the variation of sound velocity with hydrostatic pressure for oleic acid is evaluated up to 350MPa. During the measurement, we identified the phase transformation of oleic acid and the presence of the hysteresis of the dependence of sound velocity on pressure. From the performed measurements, it can be seen that the dependence of sound velocity on pressure can be used to investigate phase transformations in natural oils. Ultrasonic waves were excited and detected using piezoelectric LiNbO3(Y36 cut) 5MHz transducers. The phase velocity of the longitudinal ultrasonicwaveswas measured using a crosscorrelation method to evaluate the time of flight. Słowa kluczowe: Sound velocity, oleic acid, high pressure, phase transition Afiliacje autorów:
 25p.  
21.  Kiełczyński P., Szalewski M., Balcerzak A., Rostocki A.J.^{♦}, Tefelski D.B.^{♦}, Application of SH surface acoustic waves for measuring the viscosity of liquids in function of pressure and temperature, Ultrasonics, ISSN: 0041624X, Vol.51, No.8, pp.921924, 2011 Streszczenie: Viscosity measurements were carried out on triolein at pressures from atmospheric up to 650 MPa and in the temperature range from 10 C to 40 C using ultrasonic measuring setup. Bleustein–Gulyaev SH surface acoustic waves waveguides were used as viscosity sensors. Additionally, pressure changes occurring during phase transition have been measured over the same temperature range. Application of ultrasonic SH surface acoustic waves in the liquid viscosity measurements at high pressure has many advantages. It enables viscosity measurement during phase transitions and in the highpressure range where the classical viscosity measurement methods cannot operate. Measurements of phase transition kinetics and viscosity of liquids at high pressures and various temperatures (isotherms) is a novelty. The knowledge of changes in viscosity in function of pressure and temperature can help to obtain a deeper insight into thermodynamic properties of liquids. Słowa kluczowe: SH surface acoustic waves, Viscosity, High pressure, Phase transitions Afiliacje autorów:
 25p.  
22.  Kiełczyński P., Szalewski M., An inverse method for determining the elastic properties of thin layers using Love surface waves, INVERSE PROBLEMS IN SCIENCE AND ENGINEERING, ISSN: 17415977, Vol.19, No.1, pp.3143, 2011 Streszczenie: Estimation of the mechanical and geometrical parameters of thin coatings and surface layers in materials is of great practical importance in engineering and technology. Indeed, surface properties of many vital engineering components, such as turbine blades, pistons, or bearings, directly affect longevity and safety of the modern machinery. In this article, the authors present a novel inversion procedure for simultaneous determination of thickness, shear elastic constant, and density of thin coating layers in materials. The inversion procedure is based on measurements of the dispersion curve for surface acoustic waves of the Love type. The inverse problem is formulated as an optimization problem with the appropriately designed objective function, depending on the material parameters of the coating layer, ultrasonic frequency, and the experimental data, i.e. measured phase velocity of the surface Love wave. The minimization of the objective function provides three parameters of a thin layer, i.e. its thickness, shear elastic constant, and density. The proposed inverse method was checked experimentally for different layered structures, such as copper layer on steel substrate or ceramicsonceramics. The agreement between the results of calculations with the proposed inversion method and the experimental data was good. Słowa kluczowe: Inverse problems, Love surface waves, elastic constants, acoustic wave dispersion, thin layers Afiliacje autorów:
 20p.  
23.  Rostocki A.J.^{♦}, Siegoczyński R.M.^{♦}, Kiełczyński P., Szalewski M., An application of Love SH waves for the viscosity measurement of triglycerides at high pressures, HIGH PRESSURE RESEARCH, ISSN: 08957959, Vol.30, No.1, pp.8892, 2010 Streszczenie: A new ultrasonic method of viscosity measurement at a highpressure condition has been presented. The method is based on the Love wave amplitude measurement. The same electronic setup as in the Bleustein– Gulyaev (B–G)wave method applied by the authors recently for a highpressure measurementwas adopted. The new transducers were made of metallic materials which make them more reliable at highpressure conditions. The method has been successfully applied for the viscosity measurement of some triglycerides at highpressure conditions up to 1GPa. The results have been compared with the earlier results obtained using B–G waves. This comparison has shown that Love wave method sensors are more reliable than B–G wave sensors and cheaper in fabrication, although the sensitivity of Love wave sensors was lower. During the measurement, the phase transitions in the investigated liquids were observed. Słowa kluczowe: Love SH waves, viscosity, phase transitions, sensors Afiliacje autorów:
 27p.  
24.  Kiełczyński P., Szalewski M., Determination of the elastic properties of thin layers and graded materials using generalized Love waves, IEICE Technical Report, ISSN: 09135685, Vol.109, No.388, pp.117122, 2010 Streszczenie: The elastic properties of coatings and graded materials are very important in the design and evaluation for engineering purposes. It is well known that the velocity of the ultrasonic surface waves propagating in the layered structures and graded materials is strongly dependent on the elastic properties of the medium. Thus, by using an appropriate inverse algorithm, the elastic properties can be deduced from the measured phase velocity dispersion curves (dependence of velocity on frequency) of the surface wave. Słowa kluczowe: Inverse Problems, Love waves, elastic constants, acoustic dispersion, thin layers, graded materials Afiliacje autorów:
 
25.  Kiełczyński P., Szalewski M., Siegoczyński R.M.^{♦}, Rostocki A.J.^{♦}, New ultrasonic BleusteinGulyaev wave method for measuring the viscosity of liquids at high pressure, REVIEW OF SCIENTIFIC INSTRUMENTS, ISSN: 00346748, Vol.79, No.2, pp.261090, 2008 Streszczenie: In this paper, a new method for measuring the viscosity of liquids at high pressure is presented. To this end the authors have applied an ultrasonic method using the BleusteinGulyaev (BG) surface acoustic wave. By applying the perturbation method, we can prove that the change in the complex propagation constant of the BG wave produced by the layer of liquid loading the waveguide surface is proportional to the shear mechanical impedance of the liquid. In the article, a measuring setup employing the BG wave for the purpose of measuring the viscosity of liquids at high pressure (up to 1 GPa) is presented. The results of highpressure viscosity measurements of triolein and castor oil are also presented. In this paper the model of a Newtonian liquid was applied. Using this new method it is also possible to measure the viscosity of liquids during the phase transition and during the decompression process hysteresis of the dependence of viscosity on pressure. Słowa kluczowe: BleusteinGulyaev (BG) waves, high pressure, viscosity measurements, phase transitions Afiliacje autorów:
 
26.  Kiełczyński P., Metody ultradźwiękowe identyfikacji własności sprężystych materiałów gradientowych, INŻYNIERIA MATERIAŁOWA, ISSN: 02086247, Vol.3, pp.157164, 2008 Streszczenie: In the paper the application of the generalized shear surface waves for the determination of the elastic parameters of nonuniform Functionally Graded Materials, based on the example of steel samples subjected to the laser hardening was presented. In the article, the use of the bulk and surface ultrasonic waves for evaluation of the mechanical parameters of materials is discussed. Ultrasonic methods for investigation of the material properties are nondestructive methods. This is a main advantage of the ultrasonic methods in relation to the mechanical methods used for investigation of the mechanical properties of materials. Moreover, ultrasonic methods can be computerized. Due to this reason, ultrasonic methods can be employed directly on the production line for measuring the mechanical parameters of materials. Słowa kluczowe: Love waves, Functionally Graded Materials, elastic properties, Inverse methods, nondestructive testing Afiliacje autorów:
 
27.  Kiełczyński P., Szalewski M., Compound piezoelectric cylindrical resonators as sensors of the rheological parameters of viscoelastic media, IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL, ISSN: 08853010, DOI: 10.1109/TUFFC.2007.373, Vol.54, No.6, pp.11991206, 2007 Streszczenie: The electroelastic behavior of a viscoelastically loaded layered cylindrical resonator (sensor) comprising two coupled hollow cylinders is presented. The inner cylinder is a piezoelectric ceramic tube. The outer cylinder is a nonpiezoelectric (passive) metallic cylinder. An analytical formula for the electrical admittance of a compound layered cylindrical resonator loaded with a viscoelastic liquid is established. Admittance (conductance) diagrams were obtained using a continuum electromechanical model. The established analytical formulas enable the determination of the influence of the liquid viscosity, material, and geometrical parameters of a compound cylindrical resonator on the response characteristics of the compound sensor. In the paper, the sensor implications resulting from the performed analysis are described. Moreover, the algorithm of the method developed by the authors to evaluate the rheological parameters of a viscoelastic liquid is presented. Good agreement between the theoretical results and experimental data is shown. The analysis presented in this paper can be utilized for the design and construction of cylindrical piezoelectric viscosity sensors, annular accelerometers, filters, transducers, and multilayer resonators. Słowa kluczowe: Compound piezoelectric resonators, admittance diagrams, viscosity measurements, sensors of rheological parameters Afiliacje autorów:
 
28.  Kiełczyński P., The Analog of the KanazawaGordon Formula for Cylindrical Resonators, IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL, ISSN: 08853010, DOI: 10.1109/TUFFC.2004.1367474, Vol.51, No.11, pp.13671372, 2004 Streszczenie: In this paper, a formula relating the shift in the resonant frequency of a shear piezoceramic cylindrical resonator to the viscosity of a Newtonian liquid that loads the resonator surface was established. This formula is analogous to the classical KanazawaGordon formula that describes the change in the resonant frequency of a shear planar resonator loaded with a Newtonian liquid. To this end, the author applied the perturbation method to analyze the behavior of the piezoceramic cylindrical resonators vibrating in a shear mode and loaded with a viscous liquid. The shift in resonant frequency obtained using the perturbation method (mechanical model) was compared to an exact value of the shift in resonant frequency obtained from the complete electromechanical model (admittance diagrams) that describes shear vibrations of a piezoceramic cylindrical resonator loaded with a viscous liquid. Good conformity between the two types of results obtained can prove the correctness of the analytical formulas established in this paper. The results of this work can be applied for the design and construction of viscosity sensors. Słowa kluczowe: Viscosity, Resonant frequency, Perturbation methods, Elasticity, Piezoelectric materials, Admittance, Surface acoustic waves, Vibrations, Surface impedance, Resonance Afiliacje autorów:
 
29.  Kiełczyński P., Pajewski W., Szalewski M., Balcerzak A., Measurement of the shear storage modulus and viscosity of liquids using the Bleustein–Gulyaev wave, REVIEW OF SCIENTIFIC INSTRUMENTS, ISSN: 00346748, DOI: 10.1063/1.1765760, Vol.75, No.7, pp.23622367, 2004  
30.  Kiełczyński P., Pola akustyczne przetworników i układów ultradźwiękowych o niejednorodnym rozkładzie amplitudy drgań na powierzchni (Praca habilitacyjna), Prace IPPT  IFTR Reports, ISSN: 22993657, No.5, pp.172, 1996 
Lista rozdziałów w ostatnich monografiach
1. 556  Kiełczyński P., Advances in Clinical Audiology, rozdział: Power Amplification and Frequency Selectivity in the Inner Ear: A New Physical Model, IntechOpen, 1, pp.5998, 2017 
2. 557  Kiełczyński P., Ultrasound in Food Processing: Recent Advances, rozdział: The Application of Ultrasonics for Oil Characterization, WileyBlackwell, 1, pp.116145, 2017 
3. 25  Kiełczyński P., Acoustic Waves, rozdział: Application of acoustic waves to investigate the physical properties of liquids at high pressure, Ed. D.W. Dissanayake, Sciyo, Rijeka, Croatia, pp.317340, 2010 
Prace konferencyjne
1.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Ptasznik S.^{♦}, Rostocki A.J.^{♦}, Investigation of regular and anomalous behavior of liquid media under high pressure using ultrasonic methods, 2017 IEEE, 2017 IEEE International Ultrasonics Symposium, 20170906/0909, Washington, DC (US), pp.14, 2017 Streszczenie: In many industrial technological processes, liquids are subjected to high pressures, e.g., in the high pressure food preservation. Similarly, in modern fuel injection systems for diesel engines, biofuel is subjected to a pressure up to 300 MPa. In such conditions, in liquids, highpressure phase transitions (solidification) can occur that substantially increase the density and liquid viscosity. This solidification can result in significant problems with engine failure under coldstart conditions. This is an evident recipe for disaster, since the engine and its accessories would be very likely quickly destroyed. Thus, it is important to determine at what pressures and temperatures phase transitions occur. Conventional mechanical methods for measuring physicochemical properties of liquids at these extreme conditions do not operate. By contrast, ultrasonic techniques are very suitable for measurements of hysicochemical properties of liquids at high pressure, since they are nondestructive, can be fully automated and are characterized by the absence of moving parts. The aim of this work is to study the highpressure hysicochemical properties of liquids (exemplified by a Camelina sativa  false flax oil) using novel ultrasonic methods. Słowa kluczowe: pressure; ultrasonic methods; phase transitions; Camelina sativa Afiliacje autorów:
 
2.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., The influence of rheological parameters of viscoelastic liquids on the propagation characteristics of ultrasonic Love waves, 2017 IEEE, 2017 IEEE International Ultrasonics Symposium, 20170906/0909, Washington, DC (US), pp.14, 2017 Streszczenie: Progress in materials science has led to development of new materials with improved functional characteristics. One of the new types of materials introduced into industrial practice are plastics and polymers. These materials exhibit rheological (viscoelastic) properties, which combine simultaneously the properties of liquids and solids. Due to their attractive features, such as low specific weight, high resistance to chemical agents, ease of processing, cost ffectiveness etc. these materials are widely used in chemical, automotive, aviation and space industry. In addition, these materials are very common in many aspects of everyday life. Thus, it is very important, both from the theoretical and practical point of view, to develop new, robust and accurate methods to measure the rheological parameters (viscosity η, elasticity μ and density ρ) of plastics and polymers. The conventional mechanical methods used so far to this end are outdated, time consuming, and cumbersome. Ultrasonic methods do not possess these disadvantages. The first step in the formulation of the Inverse Method for evaluating the rheological parameters of viscoelastic liquids is to formulate and solve the Direct SturmLiouville Problem for Love waves propagating in the investigated layered elastic aveguide loaded on its surface with various types of viscoelastic materials (e.g., liquids). The aim of this study is to develop a rigorous mathematical model (Direct SturmLiouville Problem) of propagation of shear horizontal (SH) surface Love waves in layered viscoelastic structures, i.e., in layered elastic waveguides with a guiding surface layer covered with a viscoelastic material described by KelvinVoigt, Newton and Maxwell viscoelastic models respectively Słowa kluczowe: Love waves; viscoelastic liquid; SturmLiouville problem; dispersion curves Afiliacje autorów:
 
3.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Evaluation of viscoelastic parameters of surface layers by ultrasonic Love waves, IUS 2016, IEEE International Ultrasonics Symposium, 20160918/0921, Tours (FR), DOI: 10.1109/ULTSYM.2016.7728446, pp.14, 2016 Streszczenie: Simultaneous determination of the rheological parameters of viscoelastic surface layers is very important in many applications such as: sensors, geophysics, seismology, and in the NDT of materials. Love wave energy is concentrated near the waveguide surface, so that Love waves are especially suited to study the material properties of surface layers. In this work, the Direct SturmLiouville Problem for the Love wave propagation in a layered viscoelastic waveguide have been presented and solved. Next, the Inverse Problem was created and solved as an Optimization Problem. The adequately formulated objective function that depends on the elastic and viscoelastic parameters of a waveguide of the Love wave and the experimental data was used. The solution of the Inverse Problem allows to determine unknown values of the viscosity and shear elasticity of a viscoelastic medium from measurements of the dispersion curves of Love waves. Słowa kluczowe: Love waves, rheological properties, viscoelastic materials, inverse problems, viscosity, shear elasticity Afiliacje autorów:
 
4.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Rostocki A.J.^{♦}, Ptasznik S.^{♦}, Investigation of highpressure phase transitions in biofuels by means of ultrasonic methods, IUS 2016, IEEE International Ultrasonics Symposium, 20160918/0921, Tours (FR), DOI: 10.1109/ULTSYM.2016.7728444, pp.14, 2016 Streszczenie: The fundamental goal of this work is to verify the hypothesis of the existence of highpressure phase transitions in biofuel components on the example of rapeseed fatty acid methyl esters (RME), by using ultrasonic methods. in a wide range of pressures (from atmospheric pressure to 300 MPa) and for various temperatures from 5 to 20 °C. Investigation of phase transitions in biofuels at high pressures is of great importance in the design of injection systems in modern diesel engines (common rail). Direct examination of phase transitions in liquids under high pressure, using classical methods, is very difficult. To overcome this disadvantage, the authors applied ultrasonic methods (viscosity measurement), which in contrast to the classical methods allow in a relatively simple way the investigation of highpressure properties of liquids. Viscosity was measured by the original method that uses ultrasonic surface waves of the BleusteinGulyaev type, developed by the authors at the Institute of Fundamental Technological Research in Warsaw. From the measured viscosity isotherms, the occurrence of highpressure phase transitions in methyl esters were evaluated. Słowa kluczowe: highpressure phase transitions, biofuels, ultrasonic BleusteinGulyaev waves, viscosity measurements Afiliacje autorów:
 
5.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Inverse method for evaluation of elastic parameters in functionally graded materials using ultrasonic Love wave, IUS 2015, IEEE International Ultrasonics Symposium, 20151021/1024, Taipei (TW), DOI: 10.1109/ULTSYM.2015.0344, pp.14, 2015 Streszczenie: The aim of this study was to evaluate the inverse procedure to determine profiles (as a function of depth) of the mechanical properties of inhomogeneous FGM resulting from the application of various technological processes of surface treatment. First, the Direct SturmLiouville Problem for Love waves propagating in elastic graded materials with various profiles of the shear stiffness as a function of the distance from the surface, has been solved using the Finite Difference Method and Transfer Matrix Method (HaskellThompson method). Love wave dispersion curves were evaluated in the frequency range from 4 to 23 MHz. The Inverse Problem was formulated as an Optimization Problem with appropriately constructed objective function that depended on the material properties of an elastic waveguide of the Love wave and the experimental data. To minimize the considered objective function, optimization procedures of the NelderMead type from Scilab software package were employed. Słowa kluczowe: Love waves, Inverse Methods, Functionally Graded Materials, Elastic parameters, SturmLiouville Problem Afiliacje autorów:
 
6.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Rostocki A.J.^{♦}, Siegoczyński R.M.^{♦}, Ptasznik S.^{♦}, Ultrasonic studies of physicochemical parameters of biofuels in a broad range of pressures and temperatures, IUS 2015, IEEE International Ultrasonics Symposium, 20151021/1024, Taipei (TW), DOI: 10.1109/ULTSYM.2015.0345, pp.14, 2015 Streszczenie: The aim of the study was to investigate the phase transitions in biofuel components by using ultrasonic methods on the example of methyl esters of fatty acids, in a wide range of pressures (from atmospheric pressure to 400 MPa) and for various temperatures from 5 to 20 °C. Investigation of phase transitions in biofuels at high pressures is of great importance in the design of injection systems in modern diesel engines (common rail). Direct examination of phase transitions in liquids under high pressure, using classical methods, is very difficult. To overcome this disadvantage, the authors applied ultrasonic methods (viscosity measurement), which in contrast to the classical methods allow in a relatively simple way the investigation highpressure properties of liquids. Viscosity was measured by the original method that uses ultrasonic surface waves of the BleusteinGulyaev type, developed by the authors at the Institute of Fundamental Technological Research in Warsaw. From the measured viscosity isotherms, the occurrence and kinetics of highpressure phase transitions in methyl esters were evaluated. Słowa kluczowe: High pressure phase transitions, physicochemical parameters of biofuels, ultrasonic viscosity measurements, rapeseed methyl esters Afiliacje autorów:
 
7.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Density and viscosity of liquids determination using an inverse method for Love wave propagation, IUS 15, IEEE International Ultrasonics Symposium, 20140903/0906, Chicago (US), DOI: 10.1109/ULTSYM.2014.0496, pp.19921995, 2014 Streszczenie: The aim of this work was to establish an inversion procedure for the simultaneous determination of the viscosity and density of liquids. To this end, measurements of dispersion curves of the phase velocity and attenuation of shear horizontal Love waves were applied. Love waves propagate in an elastic layered waveguide covered on its surface with an investigated viscous (Newtonian) liquid. Firstly, the Direct SturmLiouville Problem of the Love wave propagation in a such waveguide was formulated and solved. Subsequently, the Inverse Problem was formulated and solved as an Optimization Problem. The appropriately constructed objective function that depends on the material properties of a waveguide of the Love wave, material properties of an investigated liquid (viscosity and density), and the experimental data was employed. The simultaneous determination of both liquid density and viscosity is important in the monitoring of technological processes in many industries (e.g. chemical, petroleum, pharmaceutical industry) as well as in geophysics. Słowa kluczowe: Love waves, Inverse Methods, Density, Viscosity of liquids , SturmLiouville Problem Afiliacje autorów:
 
8.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Rostocki A.J.^{♦}, Siegoczyński R.M.^{♦}, Ultrasonic evaluation of thermodynamic parameters of liquids under high pressure, IUS 15, IEEE International Ultrasonics Symposium, 20140903/0906, Chicago (US), DOI: 10.1109/ULTSYM.2014.0497, pp.19961999, 2014 Streszczenie: In many technological processes (e.g. in chemical, petrochemical, food and plastics industry) liquids are subjected to high pressures and temperatures. Therefore knowledge of their thermodynamic properties is essential for understanding, design and control of the process technology. Direct evaluation of thermodynamic parameters of liquids under high pressure, using conventional methods, is very difficult. Therefore, these methods are useless in industrial conditions, particularly in online control of the technological parameters of liquids. Ultrasonic methods (e.g., sound speed measurements) due to their simplicity and accuracy are very suitable for this purpose. The sound velocity is closely related with numerous thermodynamic properties of liquids. In this paper we report ultrasonic velocity and density measurements (performed by the authors) in diacylglycerol (DAG) oil over a range of pressures and temperatures. On the basis of experimental results (the sound velocity and liquid density versus pressure and temperature) the thermal expansion coefficient, specific heat capacity at constant pressure, isothermal and adiabatic compressibility of DAG oil were calculated as a function of pressure and temperature. Słowa kluczowe: Themodynamic parameters of liquids, high pressure, ultrasonic velocity, density, compressibility Afiliacje autorów:
 
9.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Rostocki A.J.^{♦}, Siegoczyński R.M.^{♦}, Thermodynamic method for measuring the B/A nonlinear parameter under high pressure, IUS 2013, IEEE International Ultrasonics Symposium, 20130721/0725, Praga (CZ), DOI: 10.1109/ULTSYM.2013.0424, Vol.1, pp.16651667, 2013 Streszczenie: The nonlinearity parameter B/A is a measure of the nonlinearity of the equation of state for a fluid. It plays a significant role in acoustics, from underwater acoustics to biology and medicine. The nonlinearity parameter is important because it determines distortion of a finite amplitude wave propagating in the fluid. Moreover, it can be related to the molecular dynamics of the medium and it can to provide information about structural properties of medium, internal pressures, clustering, intermolecular spacing, etc. Importance of the B/A parameter increases with the development of highpressure technologies. The thermodynamic method has been applied for determination of B/A parameter in diacylglycerol (DAG) oil as a function of pressure at various temperatures. Słowa kluczowe: Nonlinearity parameter B/A, Thermodynamic method, ultrasoniv velocity, high pressure, Afiliacje autorów:
 
10.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., Rostocki A.J.^{♦}, Siegoczyński R.M.^{♦}, Ptasznik S.^{♦}, Ultrasonic investigation of physicochemical properties of liquids under high pressure, IUS 2013, IEEE International Ultrasonics Symposium, 20130721/0725, Praga (CZ), DOI: 10.1109/ULTSYM.2013.0414, Vol.1, pp.16261629, 2013 Streszczenie: High pressure research of the physicochemical properties of liquids has been stimulated by the fast development of such technologies as biodiesel production, highpressure food processing and conservation, modification of biotechnological properties. Monitoring and studying liquid viscosity and ultrasonic wave velocity in liquids as a function of pressure and temperature enable to evaluate many important physicochemical parameters of liquids. These methods allow also insight into the phenomena governing the microstructural modifications occurring in treated substances, i.e. phase transitions. The knowledge of physicochemical properties (e.g. density, relaxation time, internal pressure or free volume) of pressurized substances is essential for understanding, design and control of the process technology. Measurements were conducted on the example of diacylglycerol oil (DAG oil), that is an important constituent of oils and fats. Słowa kluczowe: Physicochemical parameters of liquids, high pressure, ultrasonic velocity, viscosity of liquids, DAG oil Afiliacje autorów:
 
11.  Kiełczyński P., Szalewski M., Balcerzak A., Malanowski A.^{♦}, Rostocki A.J.^{♦}, Application of the BleusteinGulyaev wave method for investigation of highpressure phase transitions in diacylglycerol oil, IUS 2012, IEEE International Ultrasonics Symposium, 20121007/1010, Dresden (DE), DOI: 10.1109/ULTSYM.2012.0127, pp.511514, 2012 Streszczenie: Phase transitions in diacylglycerol (DAG) oil were investigated by using an ultrasonic method for measuring viscosity. Viscosity of DAG oil was measured over a wide range of hydrostatic pressures up to 500 MPa, and at temperatures ranging from 10 to 40 °C. The observed discontinuities in the viscosity versus pressure curves (isotherms) indicate phase transitions. An original ultrasonic method that uses the surface acoustic BleusteinGulyaev (BG) wave was employed to measure the viscosity of DAG oil at high pressure range. This method allowed for fast and reliable measurement of DAG oil viscosity along various isotherms. Moreover, the kinetics of the observed phase transformations at various temperatures was analyzed. Słowa kluczowe: Viscosity, Temperature measurement, Ultrasonic variables measurement, Acoustics, Pressure measurement, Acoustic measurements, Liquids Afiliacje autorów:
 
12.  Kiełczyński P., Szalewski M., Balcerzak A., Inverse problem of the Love wave propagation in elastic waveguides loaded with a viscous liquid, IUS 2012, IEEE International Ultrasonics Symposium, 20121007/1010, Dresden (DE), DOI: 10.1109/ULTSYM.2012.0375, pp.15011504, 2012 Streszczenie: The problem of propagation of Love waves in elastic waveguides loaded on the surface by a viscous (Newtonian) liquid is important in many applications such as geophysics, seismology, investigation of the physical properties of liquids. Love wave energy is concentrated near the waveguide surface, so that Love waves are especially suited to study the material properties of surface layers. In this work, the direct problem and the inverse problem of the Love wave propagation in a layered elastic waveguides loaded with a viscous liquid have been formulated and solved. The inverse problem relies on the determination of the material parameters (e.g., the unknown value of liquid viscosity) from measurements of the dispersion curves of Love waves. Słowa kluczowe: Liquids, Viscosity, Inverse problems, Surface waves, Dispersion, Linear programming, Liquid waveguides Afiliacje autorów:
 
13.  Kiełczyński P., Szalewski M., Balcerzak A., Rostocki A.J.^{♦}, Measurements of the viscosity of liquids in function of pressure and temperature using SH surface acoustic waves, IUS 2011, IEEE International Ultrasonics Symposium, 20111018/1021, Orlando (US), DOI: 10.1109/ULTSYM.2011.0129, pp.535538, 2011 Streszczenie: Triolein viscosity was measured at pressures from atmospheric up to 650 MPa and in the temperature range from 10° C to 40° C using ultrasonic measuring setup. BleusteinGulyaev SH surface acoustic waves waveguides were used as viscosity sensors. Application of SH surface acoustic waves in the liquid viscosity measurements at high pressure has many advantages. It enables viscosity measurement during phase transitions and in the highpressure range where the classical viscosity measurement methods cannot operate. The knowledge of changes in viscosity in function of pressure and temperature can help to obtain a deeper insight into thermodynamic properties of liquids. Measurements of phase transition kinetics and viscosity of liquids at high pressures and various temperatures (isotherms) is a novelty. Słowa kluczowe: Temperature measurement, Viscosity, Liquids, Ultrasonic variables measurement, Acoustic measurements, Pressure measurement, Acoustics Afiliacje autorów:
 
14.  Kiełczyński P., Szalewski M., Inverse determination of thickness and elastic properties of thin layers and graded materials using generalized Love waves, IUS 2010, IEEE International Ultrasonics Symposium, 20101011/1014, San Diego (US), DOI: 10.1109/ULTSYM.2010.5935480, pp.22352238, 2010 Streszczenie: Determination of the mechanical and geometrical parameters of thin coatings and surface layers in materials is of great practical importance in engineering and technology. In this work the authors present a novel inversion procedure for simultaneous determination of thickness, shear elastic constant and density of thin coating layers in materials. The inversion procedure is based on measurements of the dispersion curve for Love surface acoustic waves. The inverse problem is formulated as an optimization problem with the appropriately designed objective function, depending on the material parameters of the coating layer, ultrasonic frequency, and the experimental data, i.e., measured phase velocity of the surface Love wave. The minimization of the objective function provides three parameters of a thin layer, i.e., its thickness, shear elastic constant and density. The agreement between the results of calculations with the proposed inversion method and the experimental data was good. Słowa kluczowe: Inverse problems, Dispersion, Surface waves, Substrates, Copper, Coatings Afiliacje autorów:
 
15.  Kiełczyński P., Szalewski M., Rostocki A.J.^{♦}, Zduniak M.^{♦}, Siegoczyński R.M.^{♦}, Balcerzak A., Investigation of HighPressure Phase Transitions in Vegetable Oils by Measuring Phase Velocity of Longitudinal Ultrasonic Waves, IUS 2009, IEEE International Ultrasonics Symposium, 20090920/0923, Rzym (IT), DOI: 10.1109/ULTSYM.2009.5441766, pp.15631566, 2009 Streszczenie: Monitoring and studying the pressure effect on liquid properties are becoming increasingly important in food, chemical, cosmetic and pharmaceutical industry as well as in laboratory practice. Accurate thermodynamic data in liquids as a function of pressure are required for studies the structure of liquids as well as for various engineering applications. Direct measurement of thermodynamic parameters is very difficult. The velocity of sound is related to many thermodynamic parameters and can be measured relatively simple. In this work the variation of sound velocity and isothermal compressibility with hydrostatic pressure for triolein is evaluated up to 650 MPa. During the measurement we stated the phase transformation of triolein and the presence of the hysteresis of the dependence of sound velocity on pressure. To the authors' knowledge, the measurement of the sound velocity of liquids under high pressure during the phase transition is the novelty. From the performed measurements it results that the dependence of sound velocity on pressure can be used to investigate phase transformations in natural oils. Słowa kluczowe: Vegetable oils, Velocity measurement, Phase measurement, Ultrasonic variables measurement, Thermodynamics, Liquids, Pressure measurement, Chemical industry, Monitoring, Pressure effects Afiliacje autorów:
 
16.  Rostocki A.J.^{♦}, Siegoczyński R.M.^{♦}, Kiełczyński P., Szalewski M., High pressure changes of the castor oil viscosity by ultrasonic method, 21st AIRAPT/45th EHPRG International Conference on High Pressure Science and Technology, 20070917/0921, Pisa (IT), DOI: 10.1088/17426596/121/4/142009, Vol.121, pp.14200914, 2008 Streszczenie: The pressure change of viscosity of castor oil have been measured by ultrasonic method within the range of pressure up to 0.9 GPa. For the measurement, the authors have applied a new ultrasonic method based on BleusteinGulyaev (BG) waves. For the lower pressures (up to 0.3 GPa) the results have been compared with earlier results obtained by falling body method, whereas for the higher pressure range results were compared with those obtained by the flow type viscometer. The measurements have shown: 1. Exponential rise of viscosity with pressure up to 0.4 GPa according to the Barus formula. 2. Extraordinary increment of viscosity at constant pressure during phase transition. 3. The decomposition of the high pressure phase during the decompression process have shown very large hysteresis of viscosity on pressure. 4. After the decompression process the viscosity lasts higher then a initial value for several hours. Słowa kluczowe: BleusteinGulyaev (BG) waves, high pressure, phase transitions, viscosity measurements Afiliacje autorów:
 
17.  Siegoczyński R.M.^{♦}, Rostocki A.J.^{♦}, Kiełczyński P., Szalewski M., A viscosity measurement during the hight pressure phase transition in triolein, 21st AIRAPT/45th EHPRG International Conference on High Pressure Science and Technology, 20070917/0921, Pisa (IT), DOI: 10.1088/17426596/121/4/142010, Vol.121, pp.14201015, 2008 Streszczenie: The highpressure properties of triolein, a subject of extensive research at the Faculty of Physics of Warsaw University of Technology (WUT) has been enhanced by the results of viscosity measurements within the pressure range up to 0.8 GPa. For the measurement the authors have adopted a new ultrasonic method based on BleusteinGulyaev waves, successfully developed earlier for the low pressures in the Section of Acoustelectronics of the Institute of Fundamental Technological Research. The measurements have shown: 1) Exponential rise of viscosity with pressure up to 0.5 GPa. 2) Extraordinary increment of viscosity at constant pressure during phase transition. 3) Further exponential rise of viscosity with pressure of the highpressure phase of triolein. 4) The pressure exponents of the viscosity of both phases were different (the highpressure phase had much smaller exponent). 5) The decomposition of the highpressure phase due to the slowdecompression has shown very large hysteresis of viscosity on pressure dependence. Słowa kluczowe: BleusteinGulyaev (BG) waves, highpressure phase transitions, viscosity measurements, triolein Afiliacje autorów:
 
18.  Kiełczyński P., Szalewski M., Rostocki A.J.^{♦}, Gładysz J.^{♦}, Investigation of HighPressure Phase Transitions in Castor Oil Using SH Surface Acoustic Waves, IUS 2008, IEEE International Ultrasonics Symposium, 20081102/1105, Beijing (CN), DOI: 10.1109/ULTSYM.2008.0533, pp.21542157, 2008 Streszczenie: Measurement techniques for insitu rheological investigations under high pressure allow insight into the phenomena governing the microstructural modifications. The conventional mechanical methods can not be operated to this aim due to their inherent limitations. This is why ultrasonic methods for the measurement of the viscosity of liquids under high pressure were introduced. To this end, the authors have applied new ultrasonic methods, i.e., the Love wave method and the BleusteinGulyaev (BG) wave method. The measurements of the viscosity of liquid (castor oil) were carried out in function of hydrostatic pressure up to 800 MPa. During the measurement we stated the phase transformation of castor oil and the presence of the hysteresis of the dependence of viscosity on pressure. To the authors' knowledge, the measurement of the viscosity of liquids under high pressure during the phase transition and during the decompression process is the novelty. Słowa kluczowe: Petroleum, Surface acoustic waves, Acoustic waves, Pressure measurement, Viscosity, Ultrasonic variables measurement, Liquids, Phase measurement, Measurement techniques, Rheology Afiliacje autorów:
 
19.  Kiełczyński P., Pajewski W., Szalewski M., Layered Cylindrical Viscosity Sensors, IEEE International Ultrasonic Symposium, 20040823/0827, Montréal (CA), DOI: 10.1109/ULTSYM.2004.1418120, Vol.1, pp.15731576, 2004 Streszczenie: The electroelastic behavior of a viscoelastically loaded layered cylindrical resonator comprising of two coupled hollow cylinders is presented. The inner cylinder is piezoelectric. The outer cylinder is a nonpiezoelectric (passive) metallic cylinder. Analytical formulas for the elements of the impedance matrix Z of a cylindrical piezoelectric resonator vibrating in a shear mode are established. Moreover, analytical formulas for the electrical admittance of a compound layered cylindrical resonator loaded with a viscoelastic liquid are established. Admittance diagrams obtained using: (1) a continuum electromechanical model; and (2) the elements of the impedance matrix Z are exactly the same. The analysis presented in this paper can be utilized for the design and construction of cylindrical piezoelectric viscosity sensors, annular accelerometers, filters, transducers and multilayer resonators. Słowa kluczowe: Viscosity, Elasticity, Chemical sensors, Piezoelectric materials, Admittance, Surface impedance, Mechanical sensors, Equations, Electromechanical sensors, Accelerometers Afiliacje autorów:
 
20.  Kiełczyński P., Pajewski W., Szalewski M., Impedance Matrix and its Use for Modeling Axially Polarized Piezoceramic Cylindrical Resonators, IEEE International Frequency Control Symposium and PDA Exhibition Jointly with the 17th European Frequency and Time Forum, 20030504/0508, Tampa (US), DOI: 10.1109/FREQ.2003.1275188, Vol.1, pp.757760, 2003 Streszczenie: Analytical formulas for the elements of the impedance matrix Z of a cylindrical piezoelectric resonator vibrating in a shear mode are established. The input impedance was calculated employed the established elements of the impedance matrix Z. The analysis presented in this paper can be utilized for the design and construction of the cylindrical piezoelectric sensors, transducers and multilayer resonators. Słowa kluczowe: Surface impedance, Piezoelectric materials, Ceramics, Vibrations, Equations, Electromechanical sensors, Piezoelectric transducers, Mechanical sensors, Piezoelectric polarization, Viscosity Afiliacje autorów:

Abstrakty konferencyjne
1.  Kiełczyński P., Love Surface Wave Biosensors, 12th TOIN International Symposium on Biomedical Engineering, 20171111/1111, Yokohama (JP), pp.2123, 2017 Streszczenie: In this presentation I will address a fascinating example of a beneficiary interdisciplinary research. To be more specific, I will consider mutual interactions between the biosensor technology and seismology, two vital domains of research with huge practical importance in the life of modern Japanese society. I would like to convey a message that developments made in one scientific (engineering) domain can be very useful in another field of research, and viceversa. Such mutual influence of different branches of science (engineering) can significantly accelerate progress in the considered domains of R&D activities. In this presentation I will focus on one type of acoustic (ultrasonic) sensors, i.e., those employing Love surface waves, first discovered in seismology in 1911 by the British mathematician A. E. H. Love. Since the ultrasonic sensors employing Love surface waves emerged some 80 years later, in the paper published by the author in 1989, it is not surprising that many theoretical and experimental techniques were first developed in seismology and then transferred to the sensor technology. The mathematical formalism describing seismic Love waves and those used in biosensor technology is in principle the same, i.e., it uses the theory of the SturmLiouville problem, deeply rooted in functional analysis, in particular the spectral theory of compact operators and Hilbert space. Seismic Love waves can travel thousands of kilometers around the surface of the Earth and have the frequency range ~0.0110 Hz. On the other hand, those used in biosensor technology are of much higher frequencies (~50500 MHz) but travel accordingly shorter distances (~550 mm) in manmade waveguides. It should be noticed that seismic Love surface waves are main contributors to devastating consequences in aftermath of earthquakes. On the other hand, Love wave biosensors offer a unique possibility for measurements of a large number of very important properties of biological materials. Słowa kluczowe: Love waves, Sensors, Biosensors, Chemosensors, Viscosity sensors Afiliacje autorów:
 
2.  Kiełczyński P., Szalewski M., Balcerzak A., Wieja K., The influence of rheological parameters of viscoelastic liquids on the propagation characteristics of ultrasonic Love waves, 2017 IEEE, 2017 IEEE International Ultrasonics Symposium, 20170906/0909, Washington, DC (US), pp.415, 2017 Streszczenie: Progress in materials engineering has led to development of new materials with improved functional characteristics. One of the new types of Słowa kluczowe: Love waves, Rheological parameters, Rheological models, Polymers Afiliacje autorów:
 
3.  Kielczynski P., Ptasznik S.^{♦}, Szalewski M., Balcerzak A., Wieja K., Rostocki A.J.^{♦}, Investigation of regular and anomalous behavior of liquid media under high pressure using ultrasonic methods, 2017 IEEE, 2017 IEEE International Ultrasonics Symposium, 20170906/0909, Washington, DC (US), pp.417, 2017 Streszczenie: Background, Motivation and Objective Słowa kluczowe: High pressure, Biofuels, Viscosity, Phase transitions Afiliacje autorów:
 
4.  Kiełczyński P., Application of ultrasonic methods for the investigation of physicochemical parameters of edible oils, 25th Jubilee International Scientific Conference, Progress in Technology of Vegetable Fats, 20170531/0602, Rynia (PL), pp.3738, 2017 Streszczenie: The presentation includes an overview of the ultrasonic methods used to investigate the physicochemical properties of edible oils in the high pressure range. Słowa kluczowe: Ultrasonic methods, Physicochemical properties of oils Afiliacje autorów:
