Change search
Link to record
Permanent link

Direct link
BETA
Publications (10 of 27) Show all publications
Liu, Z., Rumpler, R. & Feng, L. (2019). Investigation of the sound transmission through a locally resonant metamaterial cylindrical shell in the ring frequency region. Journal of Applied Physics, 125(11), Article ID 115105.
Open this publication in new window or tab >>Investigation of the sound transmission through a locally resonant metamaterial cylindrical shell in the ring frequency region
2019 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 125, no 11, article id 115105Article in journal (Refereed) Published
Abstract [en]

Locally resonant metamaterial flat panels have proved to potentially exhibit extraordinary sound transmission loss properties when the resonance frequency of the resonators is tuned to the coincidence frequency region. Whether this technique is also effective to address the ring frequency effect for curved panels is investigated in this paper. For this purpose, a cylindrical shell, as a representation of curved panels, is studied from a theoretical and numerical point of view, with a specific focus on the transmission loss behaviour around the ring frequency region when the shell is mounted with local resonators. The influence from the resonators is presented and compared with that for a flat panel. An inverse effect of the resonators is observed on the sound transmission loss between the metamaterial cylindrical shell and the metamaterial flat panel when the resonance frequency of the resonators is tuned to be below or above the ring or coincidence frequency, respectively. Rather than the extraordinary improvement observed for the metamaterial flat panel, tuning such conventional resonators to the ring frequency of curved panels generates two side dips despite a sharp improvement at the ring frequency itself. This phenomenon is explained from an effective impedance point of view developed in this paper. The approach proposed and the conclusions provided may subsequently allow for the design of suitable resonators in order to resolve the ring frequency effect for curved panels.

Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2019
National Category
Physical Sciences
Identifiers
urn:nbn:se:kth:diva-249881 (URN)10.1063/1.5081134 (DOI)000462014300023 ()2-s2.0-85063319719 (Scopus ID)
Note

QC 20190424

Available from: 2019-04-24 Created: 2019-04-24 Last updated: 2019-04-24Bibliographically approved
Rumpler, R., Rodriguez Sanchéz, R. & Göransson, P. (2018). A multivariate, well-conditioned asymptotic waveform evaluation for finite element solutions with complex parametric dependence. In: Proceedings of ISMA 2018 - International Conference on Noise and Vibration Engineering and USD 2018 - International Conference on Uncertainty in Structural Dynamics: . Paper presented at ISMA-USD 2018.
Open this publication in new window or tab >>A multivariate, well-conditioned asymptotic waveform evaluation for finite element solutions with complex parametric dependence
2018 (English)In: Proceedings of ISMA 2018 - International Conference on Noise and Vibration Engineering and USD 2018 - International Conference on Uncertainty in Structural Dynamics, 2018Conference paper, Published paper (Refereed)
Abstract [en]

Most engineering applications involving solutions by numerical methods are dependent on several parameters, whose impact on the solution may significantly vary from one to the other. At times an evaluation of these multivariate solutions may be required at the expense of a prohibitively high computational cost. In the present work, a multivariate finite element approach is proposed, allowing for a fast evaluation of parametric responses. It is based on the construction of a reduced basis spanning a subspace able to capture rough variations of the response. The method consists in an extension of the Well-Conditioned Asymptotic Waveform Evaluation (WCAWE) to multivariate problems, by an appropriate choice of derivative sequences, and a selection of the most relevant basis components. It is validated and demonstrated for its potential on a semi-industrial sized 3D application involving coupled poroelastic and internal acoustic domains.

National Category
Fluid Mechanics and Acoustics
Identifiers
urn:nbn:se:kth:diva-240278 (URN)2-s2.0-85060386599 (Scopus ID)
Conference
ISMA-USD 2018
Funder
Swedish Research Council, 2015-04925Vinnova, 2016-05195
Note

QC 20190109

Available from: 2018-12-14 Created: 2018-12-14 Last updated: 2019-05-20Bibliographically approved
Liu, Z., Rumpler, R. & Feng, L. (2018). Broadband locally resonant metamaterial sandwich plate for improved noise insulation in the coincidence region. Composite structures, 200, 165-172
Open this publication in new window or tab >>Broadband locally resonant metamaterial sandwich plate for improved noise insulation in the coincidence region
2018 (English)In: Composite structures, ISSN 0263-8223, E-ISSN 1879-1085, Vol. 200, p. 165-172Article in journal (Refereed) Published
Abstract [en]

A new design for locally resonant metamaterial sandwich plates is proposed in this paper for noise insulation engineering applications. A systematic method to tune the resonance frequency of local resonators is developed in order to overcome the coincidence phenomenon. This method, based on an impedance approach, additionally explains the ability to overcome the antiresonance associated with these local resonators. The influence of the radiated sound from these local resonators is further investigated with finite element (FE) models, particularly in connection with the sound transmission loss (STL) of the resulting metamaterial sandwich plates. The new sandwich design proposed emerges from these analyses, encapsulating the resonators inside the core material. In addition to overcoming the coincidence effect and limiting the noise radiation by the resonators, the proposed design allows to improve the mass ratio of the metamaterial sandwich structure. This, in turn, enables to broaden the working frequency band independently of the material adopted for the resonator. The proposed metamaterial sandwich plate thus combines improved acoustic insulation properties, while maintaining the lightweight nature of the sandwich plate and its good static properties.

Place, publisher, year, edition, pages
Elsevier, 2018
Keywords
Acoustic metamaterial, Sandwich plate, Sound transmission loss, Coincidence frequency
National Category
Materials Engineering
Identifiers
urn:nbn:se:kth:diva-232743 (URN)10.1016/j.compstruct.2018.05.033 (DOI)000439466100016 ()2-s2.0-85047501239 (Scopus ID)
Funder
Swedish Research Council, 2015-04925VINNOVA, 2016-05195
Note

QC 20180807

Available from: 2018-08-07 Created: 2018-08-07 Last updated: 2019-03-08Bibliographically approved
Liu, Z., Rumpler, R. & Feng, L. (2018). Investigation on the acoustic behaviour of a locally resonant metamaterial curved panel. In: : Hiroshima Calling, ICSV 2018. Paper presented at 25th International Congress on Sound and Vibration 2018 (pp. 3409-3416). Hiroshima, 6
Open this publication in new window or tab >>Investigation on the acoustic behaviour of a locally resonant metamaterial curved panel
2018 (English)In: : Hiroshima Calling, ICSV 2018, Hiroshima, 2018, Vol. 6, p. 3409-3416Conference paper, Oral presentation with published abstract (Other academic)
Abstract [en]

In order to seek for new ways to improve the sound transmission loss at ring frequency range for curved aeronautical structures, a semi-infinite curved panel, representing aircraft fuselage, is studied in this research. First, a minor modification on Koval's classical theory for cylindrical shells is made to incorporate effective mass theory for acoustic metamaterials. Then, based on the finite element simulations, the possibility of improving the acoustic behaviour of such panels by using locally resonant acoustic metamaterial treatment is investigated. Both the host curved panel, and the host panel periodically mounted with local resonators, denoted as metamaterial curved panel, are compared from the transmission loss point of view. The observations show that the antiresonance dip appears first rather than the resonance peak in the sound transmission loss for the tested metamaterial curved panel, which may be explained by the effective impedance of the panel. The influences of the panel curvature on the dynamic behaviour of the local resonators are further discussed in comparison to the same resonantsystem acting on the flat panel. Both the finite element simulations and the theoretical estimations show the same trend, thus confirms the proposed explanation.

Place, publisher, year, edition, pages
Hiroshima: , 2018
National Category
Vehicle Engineering Fluid Mechanics and Acoustics
Identifiers
urn:nbn:se:kth:diva-244438 (URN)2-s2.0-85058798180 (Scopus ID)
Conference
25th International Congress on Sound and Vibration 2018
Note

QC 20190226

Available from: 2019-02-20 Created: 2019-02-20 Last updated: 2019-02-26Bibliographically approved
Rumpler, R., Glav, R. & Göransson, P. (2018). Off-Peak Hours Deliveries: An Acoustic Perspective on the Stockholm Pilot Study. Noise News International, 26(2), 18-20
Open this publication in new window or tab >>Off-Peak Hours Deliveries: An Acoustic Perspective on the Stockholm Pilot Study
2018 (English)In: Noise News International, ISSN 1021-643X, Vol. 26, no 2, p. 18-20Article in journal (Other (popular science, discussion, etc.)) Published
National Category
Fluid Mechanics and Acoustics
Identifiers
urn:nbn:se:kth:diva-258019 (URN)
Funder
Vinnova, 2016-05195
Note

QC 20190918

Available from: 2019-09-09 Created: 2019-09-09 Last updated: 2019-09-18Bibliographically approved
Rumpler, R. & Göransson, P. (2017). An assessment of two popular Padé-based approaches for fast frequency sweeps of time-harmonic finite element problems. Paper presented at Acoustics `17 Boston. Proceedings of Meetings on Acoustics, 30, Article ID 022003.
Open this publication in new window or tab >>An assessment of two popular Padé-based approaches for fast frequency sweeps of time-harmonic finite element problems
2017 (English)In: Proceedings of Meetings on Acoustics, ISSN 1939-800X, Vol. 30, article id 022003Article in journal (Refereed) Published
National Category
Fluid Mechanics and Acoustics
Identifiers
urn:nbn:se:kth:diva-226963 (URN)10.1121/2.0000649 (DOI)
Conference
Acoustics `17 Boston
Note

QC 20180507

Available from: 2018-04-30 Created: 2018-04-30 Last updated: 2018-05-07Bibliographically approved
Rumpler, R. & Göransson, P. (2017). Comparison of the component-wise and projection-based Padé approximant methods for acoustic coupled problems. Journal of the Acoustical Society of America, 141(5), 4033-4033
Open this publication in new window or tab >>Comparison of the component-wise and projection-based Padé approximant methods for acoustic coupled problems
2017 (English)In: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 141, no 5, p. 4033-4033Article in journal (Refereed) Published
Abstract [en]

Several Padé-based computational methods have been recently combined with the finite element method for the efficient solution of complex time-harmonic acoustic problems. Among these, the component-wise approach, which focuses on the fast-frequency sweep of individual degrees of freedom in the problem, is an alternative to the projection-based approaches. While the former approach allows for piecewise analytical expressions of the solution for targeted degrees of freedom, the projection-based approaches may offer a wider range of convergence. In this work, the two approaches are compared for a range of problems varying in complexity, size and physics. This includes for instance the modeling of coupled problems with non-trivial frequency dependence such as for the modeling of sound absorbing porous materials. Conclusions will be drawn in terms of computational time, accuracy, memory allocation, implementation, and suitability of the methods for specific problems of interest.

Place, publisher, year, edition, pages
Acoustical Society of America (ASA), 2017
National Category
Fluid Mechanics and Acoustics
Identifiers
urn:nbn:se:kth:diva-226992 (URN)10.1121/1.4989299 (DOI)
Note

QC 20180522

Available from: 2018-04-30 Created: 2018-04-30 Last updated: 2018-05-22Bibliographically approved
Liu, Z., Feng, L. & Rumpler, R. (2017). Design of broadband acoustic metamaterials for low-frequency noise insulation. In: The Journal of the Acoustical Society of America: . Paper presented at 173rd Meeting of Acoustical Society of America and 8th Forum Acusticum (pp. 3574-3574). Acoustical Society of America (ASA), 141(5)
Open this publication in new window or tab >>Design of broadband acoustic metamaterials for low-frequency noise insulation
2017 (English)In: The Journal of the Acoustical Society of America, Acoustical Society of America (ASA), 2017, Vol. 141, no 5, p. 3574-3574Conference paper, Oral presentation with published abstract (Other academic)
Abstract [en]

An innovative configuration of an acoustic sandwich structure is proposed in this paper, which uses the locally resonant structures to generate stopbands in desired frequency regions and hence to increase the sound transmission loss of the panel. Effects of different types of resonators, including the mounting techniques, are investigated. The methods to broaden the effective stopbands are discussed. The acoustic properties of the sandwich panel with non-flat laminates are also studied. Numerical analyses show that good results can be obtained when combining the laminate modification with the locally resonantstructure, especially when the stopbands are designed to compensate the corresponding coincidence effects of the sandwich panel. The analysis is based on the Finite Element models constructed in COMSOL. Bloch wave vectors are derived at first Brillouin zone by using wave expansion method. Dispersion relation of the structure is discussed. Experimental validation is planned, and the results will be shown in the conference.

Place, publisher, year, edition, pages
Acoustical Society of America (ASA), 2017
National Category
Fluid Mechanics and Acoustics
Identifiers
urn:nbn:se:kth:diva-226991 (URN)10.1121/1.4987600 (DOI)
Conference
173rd Meeting of Acoustical Society of America and 8th Forum Acusticum
Note

QC 20180507

Available from: 2018-04-30 Created: 2018-04-30 Last updated: 2019-02-26Bibliographically approved
Ericsson, A., Rumpler, R., Sjöberg, D., Göransson, P., Wellander, N. & Johansson, J. (2016). A combined electromagnetic and acoustic analysis of a triaxial carbon fiber weave for reflector antenna applications. Aerospace Science and Technology, 58, 401-417
Open this publication in new window or tab >>A combined electromagnetic and acoustic analysis of a triaxial carbon fiber weave for reflector antenna applications
Show others...
2016 (English)In: Aerospace Science and Technology, ISSN 1270-9638, E-ISSN 1626-3219, Vol. 58, p. 401-417Article in journal (Refereed) Published
Abstract [en]

Fiber composites are widely used for space applications such as antennas, solar panels and spacecraft support structures. This paper presents a combined electromagnetic and acoustic analysis of a triaxial carbon fiber weave structure, designed for ultra lightweight reflector antennas in satellite communication systems. The electromagnetic and acoustic performance of the structure are analyzed over a wide range of parametric studies, both at a microscopic and mesoscopic length scale. The electromagnetic study indicates that the main parameter governing the electromagnetic reflection performance of the weave is the electric conductivity of the carbon fibers, given that the weave structure is significantly smaller than the wavelength of the incident signals. The acoustic study identifies a critical threshold in the mesoscale geometry in order to avoid a critically high resistive behavior of the weave structure, driven by viscous effects. Design guidelines are drawn from these analyses in order to achieve a trade-off between the electromagnetic reflection properties and the resistance to acoustic loading of such composite materials. These combined analyses allow to deepen the understanding from both an electromagnetic and acoustic perspective in order to open for some new design possibilities.

Place, publisher, year, edition, pages
Elsevier, 2016
Keywords
Acoustics, Electromagnetics, Homogenization, Multi-physics analysis, Reflector antenna, Satellite communication, Carbon fibers, Economic and social effects, Fibers, Homogenization method, Reflection, Satellite antennas, Satellite communication systems, Space applications, Structural design, Weaving, Acoustic performance, Electromagnetic reflection, Mesoscopic length scale, Reflector antennas, Satellite communications, Ultra lightweights, Antenna reflectors
National Category
Fluid Mechanics and Acoustics
Identifiers
urn:nbn:se:kth:diva-195217 (URN)10.1016/j.ast.2016.08.033 (DOI)000388543700037 ()2-s2.0-84988521364 (Scopus ID)
Funder
Swedish National Space Board, 87-12
Note

QC 20161117

Available from: 2016-11-17 Created: 2016-11-02 Last updated: 2017-11-29Bibliographically approved
Rice, H., Rumpler, R. & Göransson, P. (2016). A development on fast frequency sweep methods for acoustic radiation problems. In: Proceedings of ISMA 2016 - International Conference on Noise and Vibration Engineering and USD2016 - International Conference on Uncertainty in Structural Dynamics: . Paper presented at 27th International Conference on Noise and Vibration Engineering, ISMA 2016 and International Conference on Uncertainty in Structural Dynamics, USD2016, 19 September 2016 through 21 September 2016 (pp. 521-533). KU Leuven, Departement Werktuigkunde
Open this publication in new window or tab >>A development on fast frequency sweep methods for acoustic radiation problems
2016 (English)In: Proceedings of ISMA 2016 - International Conference on Noise and Vibration Engineering and USD2016 - International Conference on Uncertainty in Structural Dynamics, KU Leuven, Departement Werktuigkunde , 2016, p. 521-533Conference paper, Published paper (Refereed)
Abstract [en]

The direct point by point swept solution of the discretised Helmholtz equation over a broad frequency range can become computationally expensive for large systems when fine frequency increments are required. Approaches involving reduced-order models using Padé-or waveform-based methods such as the well conditioned asymptotic waveform evaluation (WCAWE) can be used to significantly reduce this and can also be applied to systems with non-quadratic frequency dependency. In this paper WCAWE expansions are performed on a finite element based dynamical model of a two microphone open flanged impedance tube test. The use of an approximate loss-factor-based PML type approach to model the radiating section of the system is considered which eliminates dependency on reciprocal frequency terms. This allows for an efficient high order expansion as the frequency derivative terms need to be retained only up to second order. It is then shown that the method efficiently gives robust predictions of the end impedance with simple non-specialized elements.

Place, publisher, year, edition, pages
KU Leuven, Departement Werktuigkunde, 2016
Keywords
Acoustic impedance, Structural dynamics, Acoustic radiation, Asymptotic waveform evaluation, Broad frequency range, Frequency dependencies, Frequency increments, Reduced order models, Robust predictions, Two microphones, Finite element method
National Category
Mechanical Engineering
Identifiers
urn:nbn:se:kth:diva-216876 (URN)000392486301003 ()2-s2.0-85018176132 (Scopus ID)9789073802940 (ISBN)
Conference
27th International Conference on Noise and Vibration Engineering, ISMA 2016 and International Conference on Uncertainty in Structural Dynamics, USD2016, 19 September 2016 through 21 September 2016
Note

Conference code: 127077; Export Date: 24 October 2017; Conference Paper. QC 20171101

Available from: 2017-11-01 Created: 2017-11-01 Last updated: 2018-03-06Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-6555-531X

Search in DiVA

Show all publications