Kamil Opiela, M.Sc., Eng.

Department of Intelligent Technologies (ZTI)
position: doctoral student
telephone: (+48) 22 826 12 81 ext.: 241
room: 443
e-mail: kopiela

Recent publications
1.Opiela K.C., Zieliński T.G., Microstructural design, manufacturing and dual-scale modelling of an adaptable porous composite sound absorber, COMPOSITES PART B-ENGINEERING, ISSN: 1359-8368, DOI: 10.1016/j.compositesb.2020.107833, Vol.187, pp.107833-1-13, 2020
Abstract:

This work investigates a porous composite with modifiable micro-geometry so that its ability to absorb noise can be accommodated to different frequency ranges. The polymeric skeleton of the composite has a specific periodic structure with two types of pores (larger and smaller ones) and two types of channels (wide and narrow ones), and each of the large pores contains a small steel ball. Depending on the situation, the balls block different channels that connect the pores, and therefore alter the visco-inertial phenomena between the saturating air and solid skeleton which take place at the micro-scale level and are responsible for the dissipation of the energy of acoustic waves penetrating the porous composite. All this is studied numerically using advanced dual-scale modelling, and the results are verified by the corresponding experimental tests of 3D-printed samples. Particular attention is paid to the prototyping and additive manufacturing of such adaptive porous composites.

Keywords:

Porous composite, Adaptive sound absorber, Microstructure-based modelling, Additive manufacturing

Affiliations:
Opiela K.C.-IPPT PAN
Zieliński T.G.-IPPT PAN

Conference papers
1.Zieliński T.G., Opiela K.C., Pawłowski P., Dauchez N., Boutin T., Kennedy J., Trimble D., Rice H., Differences in sound absorption of samples with periodic porosity produced using various Additive Manufacturing Technologies, ICA 2019, 23rd International Congress on Acoustics integrating 4th EAA Euroregio 2019, 2019-09-09/09-13, Aachen (DE), DOI: 10.18154/RWTH-CONV-239456, pp.4505-4512, 2019
Abstract:

With a rapid development of modern Additive Manufacturing Technologies it seems inevitable that they will sooner or later serve for production of specific porous and meta-porous acoustic treatments. Moreover, these new technologies are already being used to manufacture original micro-geometric designs of sound absorbing media in order to test microstructure-based effects, models and hypothesis. In the view of these statements, this work reports differences in acoustic absorption measured for porous specimens which were produced from the same CAD-geometry model using several additive manufacturing technologies and 3D-printers. A specific periodic unit cell of open porosity was designed for the purpose. The samples were measured acoustically in the impedance tube and also subjected to a thorough microscopic survey in order to check their quality and look for the discrepancy reasons.

Keywords:

Sound absorption, Additive Manufacturing Technologies

Affiliations:
Zieliński T.G.-IPPT PAN
Opiela K.C.-IPPT PAN
Pawłowski P.-IPPT PAN
Dauchez N.-Sorbonne University Alliance (FR)
Boutin T.-Sorbonne University Alliance (FR)
Kennedy J.-Trinity College (IE)
Trimble D.-Trinity College (IE)
Rice H.-Trinity College (IE)
2.Opiela K.C., Zieliński T.G., Adaptation of the equivalent-fluid model to the additively manufactured acoustic porous materials, ICA 2019, 23rd International Congress on Acoustics integrating 4th EAA Euroregio 2019, 2019-09-09/09-13, Aachen (DE), DOI: 10.18154/RWTH-CONV-239799, pp.1216-1223, 2019
Abstract:

Recent investigations show that the normal incidence sound absorption in 3D-printed rigid porous materials is eminently underestimated by numerical calculations using standard models. In this paper a universal amendment to the existing mathematical description of thermal dispersion and fluid flow inside rigid foams is proposed which takes account of the impact of the additive manufacturing technology on the acoustic properties of produced samples. The porous material with a motionless skeleton is conceptually substituted by an equivalent fluid with effective properties evaluated from the Johnson-Champoux-Allard-Pride-Lafarge model. The required macroscopic transport parameters are computed from the microstructural solutions using the hybrid approach. A cross-functional examination of the quality (shape consistency, representative surface roughness, etc.) of two periodic specimens obtained from additive manufacturing processes is additionally performed in order to link it to the results of the multiscale acoustic modelling. Based on this study, some of the transport parameters are changed depending on certain quantities reflecting the actual quality of a fabricated material. The developed correction has a considerable influence on the predicted value of the sound absorption coefficient such that the original discrepancies between experimental and numerical curves are significantly diminished.

Keywords:

Rigid porous material, Additive manufacturing, Sound absorption

Affiliations:
Opiela K.C.-IPPT PAN
Zieliński T.G.-IPPT PAN
3.Opiela K.C., Rak M., Zieliński T.G., A concept demonstrator of adaptive sound absorber/insulator involving microstructure-based modelling and 3D-printing, ISMA 2018 / USD 2018, International Conference on Noise and Vibration Engineering / International Conference on Uncertainty in Structural Dynamics, 2018-09-17/09-19, Leuven (BE), pp.1091-1103, 2018
Abstract:

The purpose of this work is to present and investigate the concept of adaptive sound absorbers, that is, periodic porous media with modifiable micro-geometry, so that their ability of sound absorption or insulation can be changed in various frequency ranges. To demonstrate this concept, a simple periodic porous micro-geometry with small bearing balls inside pores is proposed. By a simple positioning of the periodic porous sample the gravity force is used for the small balls to close some of the windows linking the pores, changing in that way the flow path inside pores, which entails significant modifications of the relevant parameters of permeability and tortuosity. Also the viscous characteristic length is changed, while the porosity as well as the thermal characteristic length remain unchanged. Nevertheless, such significant changes of some crucial transport parameters strongly affect the overall acoustic wave propagation in the porous medium. All this is studied using an advanced dual-scale modelling as well as experimental testing of 3D-printed specimens.

Affiliations:
Opiela K.C.-IPPT PAN
Rak M.-other affiliation
Zieliński T.G.-IPPT PAN

Conference abstracts
1.Zieliński T.G., Opiela K.C., Multiscale and multiphysics modelling of an adaptive material for sound absorption, COMSOL CONFERENCE, 2018-10-22/10-24, Lausanne (CH), pp.1-2, 2018
2.Zieliński T.G., Jankowski Ł., Opiela K., Deckers E., Modelling of poroelastic media with localised mass inclusions, SAPEM'2017, SAPEM'2017 - 5th Symposium on the Acoustics of Poro-Elastic Materials, 2017-12-06/12-08, Le Mans (FR), pp.1-2, 2017