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Wolfgang Kropp - One of the best experts on this subject based on the ideXlab platform.
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Auralization model for the perceptual evaluation of Tyre–road noise
Applied Acoustics, 2018Co-Authors: Jens Forssén, Alice Hoffmann, Wolfgang KroppAbstract:© 2017 Elsevier Ltd Due to improvements in combustion-engines and use of electric-engines for cars, Tyre noise has become the prominent noise source also at lower speeds. Models exist that simulate the noise produced by a Rolling Tyre, as do models that auralize different traffic situations from basic data. In this paper, a novel auralization method is introduced, with the purpose to enable synthesis of useful car pass-by sound signals for various situations. The method is based on an established model for Tyre noise levels (SPERoN) that is combined with a validated auralization tool (LISTEN). In the LISTEN approach, source signals for Tyre–road interaction and propulsion are produced from data based on recorded pass-by sounds. In the combined model, the Tyre–road interaction data is shaped by the spectra estimated in SPERoN and synthesized back into a pass-by signal. The combined model is made to agree spectrally with measurements for a receiver at 7.5 m distance. Psychoacoustic judgments were used to compare the modelled signals with recorded signals, and the pass-by sounds for a given listener position showed promising quality and accuracy with respect to perceived pleasantness.
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Sound generation and sound radiation from Tyres
2013Co-Authors: Wolfgang Kropp, Carsten Hoever, Julia Winroth, Thomas BeckenbauerAbstract:The Tyre/road interaction model developed by Chalmers during the last years is utilised to exam both sound generation mechanisms and sound radiation properties of Rolling Tyres. The model is based on a very advanced Tyre model, a fully non-linear contact model, and a radiation model including the surface of the road. The model is successfully validated. The two main mechanisms, Tyre vibrations and air-flow related mechanisms – often called air-pumping – are analysed from measurements and from simulation results. The results indicate the strong influence of air-flow related mechanisms. Different Tyre/road combinations influence this result. The so gained insight is essential for the optimisation of Tyres and road surfaces. The simulations show that the lateral structure of the surface roughness can have strong influence on the generated sound at higher frequencies. The analysis of pass-by measurements also underlines the findings that at these frequencies, low order modes with respect to the cross section determine the sound radiation. Finally the influence of the road surface is investigated and the horn effect for a Rolling Tyre is calculated.
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On the sound radiation of a Rolling Tyre
Journal of Sound and Vibration, 2012Co-Authors: Wolfgang Kropp, Patrick Sabiniarz, Haike Brick, Thomas BeckenbauerAbstract:The sound radiation from Rolling Tyres is still not very well understood. Although details such as horn effect or directivity during Rolling have been investigated, it is not clear which vibrational modes of the Tyre structure are responsible for the radiated sound power. In this work an advanced Tyre model based on Wave Guide Finite Elements is used in connection with a contact model validated in previous work. With these tools the Tyre vibrations during Rolling on an ISO surface are simulated. Starting from the calculated contact forces in time the amplitudes of the modes excited during Rolling are determined as function of frequency. A boundary element model also validated in previous work is applied to predict the sound pressure level on a reference surface around a Tyre placed on rigid ground as function of the modal composition of the Tyre vibrations. Taking into account different modes when calculating the vibrational field as input into the boundary element calculations, it is possible to identify individual modes or groups of modes of special relevance for the radiated sound power. The results show that mainly low-order modes with relative low amplitudes but high radiation efficiency in the frequency range around 1 kHz are responsible for the radiated sound power at these frequencies, while those modes which are most strongly excited in that frequency range during Rolling are irrelevant for the radiated sound power. This fact is very essential when focusing on the design of quieter Tyres.
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Sound radiation of a Rolling Tyre
2011Co-Authors: Wolfgang Kropp, Patrick Sabiniarz, Haike Brick, Thomas BeckenbauerAbstract:In this work an advanced Tyre model based on Wave Guide Finite Elements is used in connection with a contact model and a radiation model in order to investigate the sound radiation from a Rolling Tyre. With these tools a slick Tyre Rolling on an ISO and a rough surface is simulated. Based on the calculated contact forces in the time domain the amplitudes of the modes excited during Rolling are determined as function of frequency. A boundary element model is then applied to predict the sound pressure level on a reference surface around a Tyre placed on rigid ground as function of the modal composition of the Tyre vibrations. Taking into account different modes when calculating the vibrational field as input into the boundary element calculations, it is possible to identify individual modes or groups of modes of special relevance for the radiated sound power. The results show that mainly low-order modes with relative low amplitudes but high radiation efficiency in the frequency range between 800 and 1200 Hz are responsible for the radiated sound power at these frequencies, while those modes which are most strongly excited in that frequency range during Rolling are irrelevant for the radiated sound power. This fact is very essential when focusing on the design of quieter Tyres.
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SOUND RADIATION FROM A Rolling Tyre
2011Co-Authors: Wolfgang KroppAbstract:By combining an advanced linear Tyre model based on Wave Guide Finite Elements with a state of the art non-linear and transient contact model it is possible to simulate a Tyre Rolling on a rough surface. The surface is characterised by roughness scans in parallel tracks along the Rolling direction. As output one obtains the time varying contact forces. Based on these contact forces the post-processing allows for calculating for instance the vibrations of the Tyre structure, the input power through the contact into the Tyre (which represents the Rolling resistance) or the forces at the hub. Today there is still a lack of understanding how different Tyre design parameters influence these Rolling resistance and ore Tyre/road noise generation. This lack of understanding is a clear hinder for the development of low noise Tyre with low Rolling resistance. Therefore the intention of this paper is to contribute to the clarification of this question by investigating which parts of the Tyre vibration (expressed as modes and/or waves) are responsible for the sound radiation during Rolling? From simple analysis of wave speed on Tyre-like structures such as rings or plates, it was rather soon understood that the radiation efficiency of most of the free waves is too low to explain the radiated sound power from Rolling Tyres. The only exceptions are waves with mainly in-plane motion. However due to the curvature of the Tyre structure there is a strong coupling between in-plane motion and out of plane motion. Kim and Bolton [1] suggested that these fast waves are potential significant radiators at higher frequencies. However these waves are difficult to excite. In the paper a slick Tyre Rolling on an ISO and a rough surface is simulated. Based on the calculated contact forces in the time domain the amplitudes of the modes excited during Rolling are determined as function of frequency. A boundary element model is then applied to predict the sound pressure level on a reference surface around a Tyre placed on rigid ground as function of the modal composition of the Tyre vibrations. By taking into account different modes when calculating the vibrational field as input into the boundary element calculations, it is possible to identify individual modes or groups of modes of special relevance for the radiated sound power. The results show that mainly low-order modes with relative low amplitudes but high radiation efficiency in the frequency range between 800 and 1200 Hz are responsible for the radiated sound power at these frequencies, while those modes which are most strongly excited in that frequency range during Rolling are irrelevant for the radiated sound power. This fact is in good agreement with earlier hypothesis suggested in [2]. It is also very essential when focusing on the design of quieter Tyres. References [1] Y.J. Kim, J.S. Bolton: Modelling Tyre treadband vibration. Internoise, The Hague, 4 (2001). [2] F. Wullens, W. Kropp: Wave content of the vibration field of a Rolling Tyre. Acta Acustica united with Acustica 93, 4(2007) 48-56.
Jerome Lelong - One of the best experts on this subject based on the ideXlab platform.
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Analytical solution for bending vibration of a thin-walled cylinder Rolling on a time-varying force
Royal Society Open Science, 2018Co-Authors: Alain Le Bot, G Duval, P. Klein, Jerome LelongAbstract:This paper presents the analytical solution of radial vibration of a Rolling cylinder submitted to a time-varying point force. In the simplest situation of simply supported edges and zero in-plane vibration, the cylinder is equivalent to an orthotropic pre-stressed plate resting on a visco-elastic foundation. We give the closed-form solution of vibration as a series of normal modes whose coefficients are explicitly calculated. Cases of both deterministic and random forces are examined. We analyse the effect of Rolling speed on merging of vibrational energy induced by Doppler's effect for the example of Rolling Tyre.
J. Perisse - One of the best experts on this subject based on the ideXlab platform.
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a study of radial vibrations of a Rolling Tyre for Tyre road noise characterisation
Mechanical Systems and Signal Processing, 2002Co-Authors: J. PerisseAbstract:Abstract Because Tyre–road noise represents the main noise source for light vehicles with driving speed above 60 km/h, comprehension of generation mechanism of Tyre–road noise has become a subject of major importance. In this paper, Tyre–road interaction and radial Tyre vibrations are investigated for Tyre–road noise characterisation. Experimental measurements are performed on a Rolling smooth Tyre with test laboratory facilities. Both tread band and sidewall responses of the Tyre are measured and compared to each other. High concentration of vibrations is observed in the vicinity of the contact area. Stationary radial deformation and non-stationary vibrations due to road rugosity are studied. Frequency analyses have been performed on the acceleration time signals showing the influence of the rotating speed on the vibrations level and frequency content. Finally, by integrating acceleration signal of the Tyre tread over one revolution, stationary radial displacement can be calculated and the true contact length can be estimated. This study provides us with new measurement data for comparison with mathematical modelling. It also gives a physical insight on generation mechanism of Tyre radial vibrations.
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A STUDY OF RADIAL VIBRATIONS OF A Rolling Tyre FOR Tyre–ROAD NOISE CHARACTERISATION
Mechanical Systems and Signal Processing, 2002Co-Authors: J. PerisseAbstract:Abstract Because Tyre–road noise represents the main noise source for light vehicles with driving speed above 60 km/h, comprehension of generation mechanism of Tyre–road noise has become a subject of major importance. In this paper, Tyre–road interaction and radial Tyre vibrations are investigated for Tyre–road noise characterisation. Experimental measurements are performed on a Rolling smooth Tyre with test laboratory facilities. Both tread band and sidewall responses of the Tyre are measured and compared to each other. High concentration of vibrations is observed in the vicinity of the contact area. Stationary radial deformation and non-stationary vibrations due to road rugosity are studied. Frequency analyses have been performed on the acceleration time signals showing the influence of the rotating speed on the vibrations level and frequency content. Finally, by integrating acceleration signal of the Tyre tread over one revolution, stationary radial displacement can be calculated and the true contact length can be estimated. This study provides us with new measurement data for comparison with mathematical modelling. It also gives a physical insight on generation mechanism of Tyre radial vibrations.
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A STUDY OF RADIALVIBRATIONS OF A Rolling Tyre FORTyre^ROAD NOISE CHARACTERISATION
2002Co-Authors: J. PerisseAbstract:Because Tyre–road noise represents the main noise source for light vehicles with driving speed above 60 km/h, comprehension of generation mechanism of Tyre–road noise has become a subject of major importance. In this paper, Tyre–road interaction and radial Tyre vibrations are investigated for Tyre–road noise characterisation. Experimental measurements are performed on a Rolling smooth Tyre with test laboratory facilities. Both tread band and sidewall responses of the Tyre are measured and compared to each other. High concentration of vibrations is observed in the vicinityof the contact area. Stationaryradial deformation and non-stationaryvibrations due to road rugosityare studied. Frequency analyses have been performed on the acceleration time signals showing the influence of the rotating speed on the vibrations level and frequencycontent. Finally , byintegrating acceleration signal of the Tyre tread over one revolution, stationary radial displacement can be calculated and the true contact length can be estimated. This studyprovides us with new measurement data for comparison with mathematical modelling. It also gives a physical insight on generation mechanism of Tyre radial vibrations.
Alain Le Bot - One of the best experts on this subject based on the ideXlab platform.
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Analytical solution for bending vibration of a thin-walled cylinder Rolling on a time-varying force
Royal Society Open Science, 2018Co-Authors: Alain Le Bot, G Duval, P. Klein, Jerome LelongAbstract:This paper presents the analytical solution of radial vibration of a Rolling cylinder submitted to a time-varying point force. In the simplest situation of simply supported edges and zero in-plane vibration, the cylinder is equivalent to an orthotropic pre-stressed plate resting on a visco-elastic foundation. We give the closed-form solution of vibration as a series of normal modes whose coefficients are explicitly calculated. Cases of both deterministic and random forces are examined. We analyse the effect of Rolling speed on merging of vibrational energy induced by Doppler's effect for the example of Rolling Tyre.
Patrick Le Tallec - One of the best experts on this subject based on the ideXlab platform.
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Newton-Krylov method for computing the cyclic steady states of evolution problems in nonlinear mechanics
International Journal for Numerical Methods in Engineering, 2018Co-Authors: Ustim Khristenko, Patrick Le TallecAbstract:This work is focused on the Newton‐Krylov technique for computing the steady cyclic states of evolution problems in non‐linear mechanics with space‐time periodicity conditions. This kind of problems can be faced, for instance, in the modeling of a Rolling Tyre with a periodic tread pattern, where the cyclic state satisfies "Rolling" periodicity condition, including shifts both in time and space. The Newton‐Krylov method is a combination of a Newton nonlinear solver with a Krylov linear solver, looking for the initial state, which provides the space‐time periodic solution. The convergence of the Krylov iterations is proved to hold in presence of an adequate preconditioner. After preconditioning, the Newton‐Krylov method can be also considered as an observer‐controller method, correcting the transient solution of the initial value problem after each period. Using information stored while computing the residual, the Krylov solver computation time becomes negligible with respect to the residual computation time. The method has been analyzed and tested on academic applications and compared to the standard evolution (fixed point) method. Finally, it has been implemented into the Michelin industrial code, applied to a full 3D Rolling Tyre model.
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Newton-Krylov method for computing the cyclic steady states of evolution problems in non-linear mechanics
International Journal for Numerical Methods in Engineering, 2018Co-Authors: Ustim Khristenko, Patrick Le TallecAbstract:This work is focused on the Newton‐Krylov technique for computing the steady cyclic states of evolution problems in non‐linear mechanics with space‐time periodicity conditions. This kind of problems can be faced, for instance, in the modeling of a Rolling Tyre with a periodic tread pattern, where the cyclic state satisfies "Rolling" periodicity condition, including shifts both in time and space. The Newton‐Krylov method is a combination of a Newton nonlinear solver with a Krylov linear solver, looking for the initial state, which provides the space‐time periodic solution. The convergence of the Krylov iterations is proved to hold in presence of an adequate preconditioner. After preconditioning, the Newton‐Krylov method can be also considered as an observer‐controller method, correcting the transient solution of the initial value problem after each period. Using information stored while computing the residual, the Krylov solver computation time becomes negligible with respect to the residual computation time. The method has been analyzed and tested on academic applications and compared to the standard evolution (fixed point) method. Finally, it has been implemented into the Michelin industrial code, applied to a full 3D Rolling Tyre model.
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Delayed feedback control method for computing the cyclic steady states of evolution problems
Computer Methods in Applied Mechanics and Engineering, 2018Co-Authors: Ustim Khristenko, Patrick Le TallecAbstract:Abstract This work is focused on fast techniques for computing the cyclic steady states of evolution problems in non-linear mechanics with space–time periodicity conditions. In industrial applications, in order to avoid the inversion of very large matrices, such a cyclic solution is usually computed as an asymptotic limit of the associated initial value problem with arbitrary initial data. However, when the relaxation time is high, convergence to the limit cycle can be very slow. In such cases nonetheless, one is not interested in the transient solution, but only in a fast access to the limit cycle. Thus, in this work we modify the problem, introducing the time-delayed feedback control, which is widely used for stabilization of unstable periodic orbits. In our framework it is applied to an initially stable system in order to accelerate its convergence to the limit cycle. Moreover, the control term, based on the space–time periodicity error, includes both shifts in time and in space. Our main result is the optimal form of the control term for a very general class of linear evolution problems, providing the fastest convergence to the cyclic solution, which has been further extended and studied in the non-linear case . Efficiency of the method increases with the problem’s relaxation time. The method has been tested using academic applications and compared to the non-controlled asymptotic convergence as well as to the Newton–Krylov shooting algorithm. Finally, the method has been implemented into the Michelin industrial code, applied to a full 3D Rolling Tyre model.
