The Numerical Simulation And Experimental Research Of Vehicular Speaker Sound Field In The Car

With the rapid development of automobile industry, the requirement of automobile’stravelling comfort is convincingly strengthened. As an important factor that influence thecar’s travelling comfort, vehicular speaker sound field has become a focus in the study ofelectronic acoustics field. The traditional research method of vehicular speaker sound field isestablished on the basis of subjective evaluation, while there is vacancy in the field ofobjective evaluation. In this paper the method of combining the EASE software simulationwith electro-acoustic testing system (the Clio) experimental measurements is raised to analyzethe coupled sound field of sample car, which is a certain type of domestic car. On the basis ofverifying the accuracy of EASE software, the optimization design for vehicular speaker soundfield of sample car is conducted.This paper applied acoustic simulation software EASE to model the sample car, setabsorption coefficient for the vehicle interior trim and to build acoustic model of vehicularspeakers. Then we simulated the reverberation time, the total sound pressure level and clarityof vehicular speakers sound field in different measure points, analyzed the sound field basedon the simulation in sample car. The transfer equation of low frequency sound in sound fieldis established based on the finite element method of wave theory, which realize the accuratecalculation of the low frequency.This paper has measured the total noise level, reverberation time, clarity and total soundpressure level of different points in the sample car by apply of the electro-acoustic test systemClio. Experimental results show that higher accuracy in the simulation of reverberation timeand clarity of vehicular speaker sound field with acoustic simulation software EASE, andgreater error in the simulation of sound pressure level in low frequency to the finite elementmethod; the range of reverberation time of sample car is larger, which resulted in the greatchange of clarity and unsatisfied listening effect; the unevenness of sound pressure level incab is relatively larger, the sound pressure level of low-frequency sound in cab is low. Based on the design principles of traditional interior trim design and speaker distribution,optimization design of the vehicle interior trim and speaker system distribution of the samplecar has been done. The EASE software simulation results show that the optimizedreverberation time of the sample car is close to the best reverberation time, the claritymaintained at-3.48dB~13.74dB, and the unevenness of sound field is less than3.11dB,which verifying the feasibility and reliability of the optimized design.