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  1. 11 Materiały Budowlane
  2. 9 Vibrations in Physical Systems
  3. 5 Czasopismo Techniczne. Mechanika
  4. 5 Technical Transactions. Mechanics
  5. 2 Autex Research Journal
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  1. 7 Sikora J.
  2. 7 Turkiewicz J.
  3. 2 Chojak Aleksandra
  4. 2 Dulak L.
  5. 2 Gardziejczyk Władysław
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  1. 4 2025
  2. 3 2024
  3. 2 2023
  4. 4 2022
  5. 2 2021
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1
Content available The influence of diffuser configuration in a reverberation room on sound absorption coefficient measurements
Mleczko Dominik
Materiały Budowlane
|
2025
|
nr 8
213--219
EN
The aim of the study was to evaluate the impact of diffuser arrangement in a reverberation room on the values of the sound absorption coefficient determined from reverberation time measurements in accordance with ISO 354. Measurements were carried out for four configurations, both with and without a sound‑absorbing sample. The results showed that the diffuser layout can affect the outcomes, particularly at low frequencies, confirming the sensitivity of the measurements to acoustic field conditions.
PL
W artykule zaprezentowano ocenę wpływu rozmieszczenia rozpraszaczy w komorze pogłosowej na wartość współczynnika pochłaniania dźwięku wyznaczanego na podstawie czasu pogłosu zgodnie z ISO 354. Badania wykonano w czterech konfiguracjach, z materiałem pochłaniającym i bez. Wykazano, że układ rozpraszaczy może wpływać na uzyskiwane wyniki, szczególnie w zakresie niskich częstotliwości, co potwierdza wrażliwość pomiarów na warunki pola akustycznego.
2
Content available Study of sound‑absorbing and insulating properties of regenerable materials to reduce noise
Świrk Patrycja, Leniowska Lucyna
Materiały Budowlane
|
2025
|
nr 8
166--172
EN
Many available sound‑absorbing materials are made from reticulated foam, fibrous, granular, or loose materials compressed together, for example, under the influence of temperature, while maintaining a porous structure. However, most of them quickly degrade under the influence of environmental conditions, temperature, humidity, etc. In this work, an acoustic metamaterial is proposed that can be used as an absorber to obtain broadband sound absorption for acoustic silencers that reduce noise emitted during the discharge of gases or the process of air. The absorbers are installed inside the acoustic silencers, where they are exposed to the turbulent flow of a potentially contaminated or viscous fluid with suspended dust particles and carried along with the flow. The aim of the research is to develop materials that are characterised by good absorption properties and that also exhibit high resistance to moisture. Several samples of granulated materials, with regular shapes and different sizes of granules were selected for the study. It was found that high humidity does not affect the acoustic properties of the considered samples and it does not cause negative changes in the material structure. The proposed material consisting of plastic granules of different diameters is resistant to moisture and can be easily regenerated in the case of severe contamination.
PL
Wiele dostępnych materiałów dźwiękochłonnych jest wykonanych z pianki o strukturze siatkowanej, włóknistej, granulowanej lub luźnej, sprasowanej razem, np. pod wpływem temperatury. W wyniku tego powstaje struktura porowata. Ulega ona jednak szybko degradacji pod wpływem warunków środowiskowych, temperatury, wilgotności itp. W artykule zaprezentowano metamateriał akustyczny, który może być stosowany jako absorber szerokopasmowego pochłaniania dźwięku w przypadku tłumików akustycznych, które redukują hałas emitowany podczas odprowadzania gazów. Absorbery są instalowane wewnątrz tłumików akustycznych. Są tam narażone na turbulentny przepływ potencjalnie zanieczyszczonego lub lepkiego płynu z zawieszonymi cząstkami pyłu i przenoszone wraz z jego przepływem. Celem przeprowadzonych badań było opracowanie materiałów charakteryzujących się dobrymi właściwościami absorpcyjnymi, a także wykazujących dużą odporność na wilgoć. Do badań wybrano kilka próbek materiałów granulopodobnych o regularnych kształtach i różnej wielkości granulek. Stwierdzono, że duża wilgotność nie wpływa na właściwości akustyczne ocenianych próbek i nie powoduje negatywnych zmian w ich strukturze. Proponowany materiał składający się z granulek tworzywa sztucznego o różnej średnicy jest odporny na wilgoć i może być łatwo regenerowany w przypadku znacznego zanieczyszczenia.
3
Content available Mobile and stationary methods for measuring and assessing of noisiness of road pavements
Gardziejczyk Władysław, Motylewicz Marek
Materiały Budowlane
|
2025
|
nr 8
81--88
EN
The type and kind of road surfaces and their technical condition have a significant impact on the tyre/road noise of motor vehicles. The paper presents possibilities and examples of the use of stationary and mobile methods for measuring and assessing the acoustic properties of pavements for three cases involving the laboratory mix design and road use stages. The results of the example studies confirmed the effectiveness of these methods in assessing the noise performance of road pavements.
PL
Typ i rodzaj nawierzchni drogowych oraz ich stan techniczny mają istotny wpływ na poziom hałasu toczenia pojazdów samochodowych. W artykule przedstawiono możliwości i przykłady wykorzystania stacjonarnych i mobilnych metod pomiaru i oceny właściwości akustycznych nawierzchni w odniesieniu do trzech przypadków obejmujących etapy projektowania mieszanek w laboratorium oraz użytkowania drogi. Wyniki przykładowych badań potwierdziły skuteczność tych metod w ocenie hałaśliwości nawierzchni drogowych.
4
Content available Application of perforated hollow blocks as sound-absorbing structures in the acoustic design of Polish Television film studios
Ziarko Bartłomiej, Łukaszewski Łukasz, Kłosak Andrzej
Materiały Budowlane
|
2025
|
nr 12
8--17
EN
The article presents the concept and results of using hollow blocks as sound-absorbing elements in the acoustic design of the interiors of the newly constructed Polish Television film studios in Warsaw. Due to budget constraints and the need to employ simple, durable, and widely available building materials, hollow blocks were adapted as an alternative to conventional acoustic treatments. The paper discusses the integration of these elements with the interior architecture, their geometric parameters, and their influence on the reverberation time within the room. It also presents the results of reverberation time measurements and sound absorption coefficient analyses, which confirmed the effectiveness of the proposed solution. The use of hollow blocks made it possible to achieve favourable acoustic conditions inside film studios while maintaining low construction costs and simplicity of implementation.
PL
W artykule przedstawiono koncepcję oraz wyniki zastosowania pustaków otworowych jako elementów dźwiękochłonnych w projekcie akustyki wnętrz nowo powstałych studiów zdjęciowych Telewizji Polskiej w Warszawie. Ze względu na ograniczenia budżetowe oraz konieczność wykorzystania prostych, trwałych i ogólnodostępnych materiałów budowlanych, pustaki otworowe zostały zaadaptowane jako alternatywa konwencjonalnych ustrojów akustycznych. Omówiono sposób integracji tych elementów z architekturą wnętrza, ich parametry geometryczne oraz wpływ na czas pogłosu w pomieszczeniu. Przedstawiono również wyniki pomiarów czasu pogłosu oraz analizy współczynnika pochłaniania dźwięku, które potwierdziły skuteczność zaprojektowanego rozwiązania. Zastosowanie pustaków otworowych umożliwiło uzyskanie korzystnych warunków akustycznych w halach zdjęciowych z zachowaniem niskich kosztów realizacji i prostoty wykonania.
5
Content available Acoustic properties of biodegradable materials in the low and medium frequency range
Świrk Patrycja, Leniowska Lucyna, Korzyńska Katarzyna
Vibrations in Physical Systems
|
2024
|
Vol. 35, nr 2
art. no. 2024208
EN
Materials commonly used in various public spaces are characterized by sound-absorbing or insulating properties. Natural fiber composites are an eco-friendly promising alternative to conventional synthetic fiber composites. For specialized rooms, it is essential to provide good insulation and properly selected sound-absorbing materials. This article presents the results of tests on the acoustic properties of selected natural, biodegradable materials. The aim of the research was to find biodegradable composites that would have good insulating and absorption properties in the low- and medium-frequency ranges. Firstly we tested several configurations of composites made of various wood-based materials in terms of sound pressure vs. frequency. Then, the sound absorption coefficients of the best natural fiber composites used were measured by the technique of two microphone transfer functions in the impedance tube. It was concluded that multi-functional composite materials can be made by natural fibers so that both the good acoustic insulation together with appropriately high sound absorption coefficients in the low and medium frequency range can be achieved.
6
Content available remote Ocena właściwości akustycznych warstwy ścieralnej z asfaltu porowatego nawierzchni drogowych w warunkach laboratoryjnych
Gardziejczyk Władysław, Motylewicz Marek, Sakowski Mariusz
Materiały Budowlane
|
2024
|
nr 6
32--35
PL
Zastosowanie asfaltu porowatego w warstwie ścieralnej nawierzchni drogowej istotnie wpływa na obniżenie poziomu hałasu opona/nawierzchnia. Parametrami charakteryzującymi właściwości akustyczne warstwy ścieralnej są współczynnik pochłaniania dźwięku i wodoprzepuszczalność. W artykule przedstawiono analizę wyników badań współczynnika pochłaniania dźwięku oraz wodoprzepuszczalności mieszanek z asfaltu porowatego. Stwierdzono istotny wpływ zawartości wolnych przestrzeni w mieszance na wartości badanych parametrów.
EN
The use of porous asphalt in the wearing course of a road pavement has a significant effect on reducing tyre/road noise levels. The parameters characterising the acoustic properties of the wearing course are sound absorption coefficient and water permeability. This paper presents an analysis of the results of a study of the sound absorption coefficient and water permeability of porous asphalt mixtures. A significant influence of the air voids content of the mixture on the values of the parameters studied was found.
7
Content available Designing of sound - absorbing seats for Jastrzebie-Zdroj concert hall
Kłosak Andrzej, Szeląg Agata
Materiały Budowlane
|
2024
|
nr 8
69--78
EN
This paper discusses the design, realization and acoustical performance of a sound-absorbing auditorium chairs intended for a concert hall with 350 seats, opened in 2022 at the Music School in Jastrzębie-Zdrój. Several construction aspects were covered: the selection of foam for the seat and upholstery fabric based on measurements of air flow resistance, as well as the influence of the fabric lamination process on the acoustic properties of the seats. The construction of the chair and the acoustic parameters of the completed seats installed in the auditorium were also described. Finally, the article described how we managed to measure the absorption coefficient of occupied seats within the constraints of human contact related to the COVID-19 pandemic.
PL
W artykule omówiono projekt, realizację oraz parametry akustyczne dźwiękochłonnych foteli audytoryjnych przeznaczonych do sali koncertowej na 350 miejsc, otwartej w 2022 r. w Szkole Muzycznej w Jastrzębiu-Zdroju. Omówiono kilka aspektów konstrukcyjnych: dobór pianki tapicerskiej i tkaniny obiciowej na podstawie pomiarów oporu przepływu powietrza, a także wpływ procesu laminowania tkaniny na właściwości akustyczne siedzisk. Opisano również konstrukcję fotela, parametry akustyczne gotowych foteli zainstalowanych w sali oraz sposób, w jaki udało się zmierzyć współczynnik pochłaniania zajętych miejsc w ramach ograniczeń, dotyczących kontaktu międzyludzkiego, związanych z pandemią COVID-19.
8
Content available The use of sound-absorbing properties of acoustic panels with different degree of perforation on the outer lining layer in modeling and calculations of traffic noise
Żuchowski Rafał, Nowoświat Artur, Pudełko Bartłomiej, Dulak Leszek
Vibrations in Physical Systems
|
2023
|
Vol. 34, nr 2
art. no. 2023219
EN
The article presents research studies on the impact of perforation of the outer lining layer of an acoustic panel used for the construction of road noise reduction devices on its absorbing properties. The research included measurements of the reverberation time in the laboratory conditions of diffusion field, on the basis of which the values of sound absorption coefficient as a function of frequency were determined. In addition, for various solutions of acoustic panels based on a corrugated fiber cement board on the top surface and on two types of mineral wool inside the panel, the αw and αp indices as well as sound absorption rating index DLαNRD were calculated. Then, computer simulations were carried out to show the influence of laboratory-determined acoustic parameters of the panels on the acoustic climate in the vicinity of a selected transport system. The key aspects of the modeling process are presented, the characteristics of the noise source and the analysis of the results are described. An important goal of traffic noise modeling is to strive to develop more friendly and sustainable material solutions that will reduce the negative effects of noise on people and the environment.
9
Content available The effect of sound-absorbing walls on the acoustic properties of the modelled unit cell of a sound-absorbing metamaterial
Chojak Aleksandra, Binek Wojciech, Chojnacki Bartłomiej, Pawlik Jan, Idczak Julia
Vibrations in Physical Systems
|
2023
|
Vol. 34, nr 2
art. no. 2023212
EN
Cavity-based metamaterials are usually designed for sound absorbing or sound scattering properties. They are built of combinations of ducts and slits, which in the case of acoustic absorbers are designed to maximize the sound absorption at resonance frequencies through the appearance of the viscothermal losses. The unit cells are designed under the assumption of perfectly rigid walls, shared by all the analytical models. Sound absorbing properties of the structures result from viscothermal losses in small ducts. The paper discusses the influence of adding sound absorption to the walls in the numerical model on the results of the observed sound absorption coefficient. It is demonstrated that the resulting sound absorption of the structure varies with changing sound absorption coefficient of the walls of the structure. The same observations are made for 3D-printed measurement samples, showing the importance of including the sound absorption of the walls in the modelling process.
10
Content available Experimental verification of similarity criteria for sound absorption of simple metamaterials
Chojak Aleksandra
Vibrations in Physical Systems
|
2022
|
Vol. 33, nr 2
art. no. 2022211
EN
The paper concerns the dimensional analysis of simple acoustic metamaterials and its experimental verification in a computer model. Due to their decreased thickness possible because of the thermoviscous losses and sound dispersion that occur in acoustic metamaterials, such structures are gaining popularity, both as sound absorbers and diffusers. This implies the need to find their equivalents to be used at scale - both for modeling interiors with metamaterials and developing more complicated structures. The paper discusses the dimensional analysis performed for a generalized unit cell of a metamaterial with a resonator. The dimensional analysis shows the need for scaling both the geometrical dimensions of the structure and the parameters of the medium - air. The dimensional analysis was derived based on the transfer matrix method and was proven correct with the finite element method model. The paper also discusses the consequences of neglecting the air criteria, which are impossible to be fulfilled. This opens the question of finding new criterial numbers allowing the correct reflection of acoustic metamaterials at scale.
11
Content available Comparative analysis of the acoustic properties of granular materials determined with the use of impedance tube
Kosała Krzysztof
Vibrations in Physical Systems
|
2022
|
Vol. 33, nr 3
art. no. 2022321
EN
The results of acoustic property tests for six types of granular materials: perlite, vermiculite, active coconut carbon, rubber granulates, pumice and wood chips, which can be used in noise protection structures, are shown in the article. The characteristics of the normal incidence sound absorption coefficient and the normal incidence sound transmission loss for material specimens with seven thicknesses in the range of 10-100 mm were determined based on the results of experimental tests carried out with the use of an impedance tube. The relationships between the first resonant absorption frequencies and the thicknesses of material specimens were determined. Single-number indices for the tested materials, in the form of the weighted sound absorption coefficients, were determined. Subsequently, dependencies of these indices on the surface mass of the tested materials were determined. The research showed that three materials, perlite, vermiculite and active coconut carbon, were distinguished among the examined granules with the best sound-absorbing and sound-insulating properties. Active coconut carbon had the best sound-insulating properties among the granular materials tested.
12
Content available Analysis of factors influencing the measurement result of the reverberant sound absorption coefficient under laboratory conditions
Czapla Marcjanna, Wszołek Tadeusz
Vibrations in Physical Systems
|
2022
|
Vol. 33, nr 1
art. no. 2022103
EN
There are still discrepancies in the measurement results despite the standardized methods of measuring the sound absorption coefficient in the reverberation room. They appear especially in interlaboratory tests. The research used the method included in the EN-ISO 354: 2003 standard to determine the sound absorption coefficient. The subject of scientific research was to investigate the impact of measurement techniques (Maximum Length Sequence method and interrupted noise method for both T20 and T30 evaluation ranges), humidity in the test room, sample seasoning and sample fitting, and finally the influence of room variability on the measurement results. The tests were performed in two reverberation chambers. The study included two types of materials. Samples (1) made of identical pieces of mineral wool (ISOVER glass wool and ROCKWOOL rock wool) and (2) of fibreboard. Mineral wool was of different thicknesses. Among the measurement techniques, the smallest dispersion of the reverberation time results was obtained with the MLS -T30 method, and the highest differences in the results were caused by the test being performed in another room (reverberation chamber). There was no significant influence with the increase in humidity or the careful arrangement of the test sample from the components on the measurement result.
13
Content available remote A Novel Theoretical Modeling for Predicting the Sound Absorption of Woven Fabrics Using Modification of Sound Wave Equation and Genetic Algorithm
Putra Valentinus Galih Vidia, Irwan, Wijayono Andrian, Mohamad Juliany Ningsih, Yusuf Yusril
Autex Research Journal
|
2022
|
Vol. 22, no. 1
108--122
EN
Woven fabric in Indonesia is generally known as a material for making clothes and it has been applied as an interior finishing material in buildings, such as sound absorbent material. This study presents a new method for predicting the sound absorption of woven fabrics using a modification of the wave equations and using genetic algorithms. The main aim of this research is to study the sound absorption properties of woven fabric by modeling using a modification of the sound wave equations and using genetic algorithms. A new model for predicting the sound absorption coefficient of woven fabric (plain, twill 2/1, rips and satin fabric) as a function of porosity, the weight of the fabric, the thickness of the fabric, and frequency of the sound wave, was determined in this paper. In this research, the sound absorption coefficient equation was obtained using the modification of the sound wave equation as well as using genetic algorithms. This new model included the influence of the sound absorption coefficient phenomenon caused by porosity, the weight of the fabric, the thickness of fabric as well as the frequency of the sound wave. In this study, experimental data showed a good agreement with the model.
14
Content available Experimental tests of the acoustic properties of sound-absorbing linings and cores of layered baffles
Kosała Krzysztof
Vibrations in Physical Systems
|
2021
|
Vol. 32, nr 1
art. no. 2021107
EN
The article presents the results of research on the acoustic properties of materials used as sound-absorbing linings and cores in baffles of anti-noise protection. Using an impedance tube the spectral characteristics of the normal incidence sound absorption and sound transmission loss indices of 12 specimens of mineral wool with different density and thickness were determined. From these characteristics, the single-number weighted sound absorption coefficient αw and the sound reduction index Rw were calculated. To calculate the value of the Rw index on the basis of surface mass of the mineral wool specimen, a new formula was proposed. The insertion loss of an acoustic enclosure with one, two and three-layer walls with dimensions of 0.7×0.7 m, containing mineral wool, was determined. The best efficiency was achieved for the enclosure made of walls of layers: mineral wool, placed on the sound source side, steel plate and aluminium plate.
15
Content available Application of the impulse response method in the test of acoustic properties of building materials
Piechowicz Janusz
Vibrations in Physical Systems
|
2021
|
Vol. 32, nr 2
art. no. 2021201
EN
Understanding the acoustic properties of the materials used in the construction of wall surfaces, plays an important role in structural and environmental acoustics. There are many research methods for determining the acoustic parameters of building elements, such as the sound absorption coefficient, the sound reflection coefficient, or the sound insulation index determined in the laboratory or in situ. This work focuses on the determination of the sound absorption coefficient and the possibility of its measurement in "in situ" conditions by the impulse response method. The main purpose of the presented research was to check whether it is possible to use the impulse method in a small reverberant room to determine the sound absorption coefficient of a small part of the wall structure.
16
Content available Assessment of sound absorbing properties of composite made of recycling materials
Gaj Patryk, Kopania Joanna, Wójciak Kamil, Bogusławski Grzegorz
Vibrations in Physical Systems
|
2019
|
Vol. 30, nr 1
art. no. 2019109
EN
In modern world we are searching methods to reuse most of industrial disposals produced during manufacturing. Some kinds of materials, like scraps from acoustic foam, however are not so easily utilized using recycling methods for its primary usage. Disposals produced during the manufacturing process can be compressed and reused as sound absorbing material. The purpose of this article is to examine sound absorbing properties of material made of acoustic foam disposals and compare it with sound protection materials, which are commonly used. Sound absorbing damping were tested using Kundt’s tube and reverberation room examination method. Tests were carried out according to standard PN-EN ISO 354:2005, for reverberation room examination, and according to Bruel&Kjaer electronic instruments technical manual for Kundt’s tube examination.
17
Content available remote Projektowanie adaptacji akustycznej otwartych pomieszczeń do prac administracyjnych. Część 1. Projektowanie podstawowe
Mikulski Witold
Materiały Budowlane
|
2019
|
nr 8
16--20
PL
Projektowanie akustyczne pomieszczeń biurowych open space polega na takim uwzględnieniu w pomieszczeniu różnych wyrobów dźwiękochłonnych, aby uzyskać wymagane przepisami warunki akustyczne. W artykule projektowanie podzielono na dwa etapy. Etap pierwszy, wymagany przez przepisy polskie, to uzyskanie w pomieszczeniu wymaganej chłonności akustycznej. Natomiast etap drugi polega na takiej aranżacji akustycznej pomieszczenia i stanowisk pracy, aby uzyskać w nim wymagane warunki propagacji (a właściwie separacji) dźwięków mowy między stanowiskami pracy. Zewzględu na objętość, artykuł podzielono na dwie części. W części pierwszej opisano pierwszy etap projektowania (podano metodę obliczeniową wg PN-B-02151-4:2015 i przykład). W części drugiej, w następnym artykule, opisany zostanie etap drugi projektowania wraz z podaniem przykładu (z wykorzystaniem programu ODEON).
EN
The acoustic design of the open plan office consists in taking into account various sound-absorbing products in the room to achieve the required acoustic conditions. In the article design is divided into two stages. The first stage, obligatory by Polish regulations, is to obtain the room's required sound absorption. The second stage consists in such an acoustic arrangement of the room and workstations to obtain the required conditions for the propagation (or actually separation) of speech sounds between workstations. Due to the volume, the article has been divided into two parts. The first part (this one) describes the first design stage (the calculation method according to PN-B-02151-4:2015 standard and example are given). In the second part, in the next article, the second design stage (using the ODEON software) will be described.
18
Content available remote Wpływ materiałów wykończeniowych na warunki akustyczne w pomieszczeniu
Olechowska M., Nowoświat A., Krause P.
Materiały Budowlane
|
2018
|
nr 12
3--5
PL
W artykule dokonano przeglądu wybranych wyrobów dźwiękochłonnych i przeanalizowano ogólne zasady ich stosowania w celu poprawy właściwości akustycznych pomieszczeń. W tym celu zestawiono wartości współczynników pochłaniania dźwięku wszystkich analizowanych wyrobów dźwiękochłonnych, a następnie zamodelowano w programie obliczeniowym ODEON przykładowe pomieszczenie, które poddawano adaptacji akustycznej (kolejno sufit, ścianę oraz podłogę) odpowiednio dobranym wyrobem wykończeniowym. Na tej podstawie określono wpływ danego wyrobu na poprawę właściwości akustycznych pomieszczenia.
EN
The article reviews selected sound absorbing products and analyzes the general principles of their use in order to improve the acoustic properties of rooms. For this purpose, the values of sound absorption coefficients of all the sound absorbing products analyzed were summarized and then, in the ODEON software, a sample room was made, which was subjected to acoustic adaptation (followed by the ceiling, wall and floor) of the primary room with a properly selected finishing product. On this basis, the impact of a given product on the improvement of the acoustic properties of the room was determined.
19
Content available remote Effect of Thickness, Density and Cavity Depth on the Sound Absorption Properties of Wool Boards
Qui H., Enhui Y.
Autex Research Journal
|
2018
|
Vol. 18, no. 2
203--208
EN
A novel wool absorption board was prepared by using a traditional non-woven technique with coarse wools as the main raw material mixed with heat binding fibers. By using the transfer-function method and standing wave tube method, the sound absorption properties of wool boards in a frequency range of 250-6300 Hz were studied by changing the thickness, density, and cavity depth. Results indicated that wool boards exhibited excellent sound absorption properties, which at high frequencies were better than that at low frequencies. With increasing thickness, the sound absorption coefficients of wool boards increased at low frequencies and fluctuated at high frequencies. However, the sound absorption coefficients changed insignificantly and then improved at high frequencies with increasing density. With increasing cavity depth, the sound absorption coefficients of wool boards increased significantly at low frequencies and decreased slightly at high frequencies.
20
Content available Effect of the composite temperature and humidity test on the sound absorption coefficient of fibrous materials used in automotive applications
Białkowski P., Zapart Ł., Krężel B.
Archiwum Motoryzacji
|
2018
|
Vol. 81, nr 3
29--38
EN
In this article an attempt to determine the effect of composite temperature and humidity test on the sound absorption coefficient for commonly used materials in vehicles is described. Three types of fibrous materials were selected. The absorption coefficient was determined for material samples and then the materials were tested with composite temperature and humidity test. After the test, the sound absorption coefficient was measured again. The difference between the absorption coefficients before and after the test shows the actual effect on the sound absorption. An impedance tube was used to determine the absorption coefficient. Results are presented in graphs and tables for three types of fibrous materials. The method of measurement is described and conclusions are drawn.
PL
W pracy przedstawiono próbę określenia wpływu temperatury i wilgotności na współczynnik pochłaniania dźwięku materiałów powszechnie stosowanych w samochodach. Do badań wybrano trzy rodzaje materiału włóknistego. Dla próbek materiału wyznaczono współczynnik pochłaniania dźwięku, a następnie próbki te poddano złożonej próbie temperatury i wilgotności. Po wykonaniu testu temperaturowo- wilgotnościowego ponownie wyznaczono współczynnik pochłaniania dźwięku. Różnica pomiędzy współczynnikami pochłaniania przed i po teście przedstawia rzeczywisty wpływ temperatury i wilgotności dla danej próbki materiału. Do wyznaczenia współczynnika pochłaniania dźwięku wykorzystano rurę impedancyjną. Wyniki przedstawiono w formie wykresów i tabel dla danego materiału. Opisano przebieg pomiarów oraz powstałe wnioski.
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