Research On The Interior Sound Quality Evaluation For Vehicle Under Accelerated Driving Condition

A-weighted sound pressure level(SPL) was usually used as a standard to evaluatethe interior noise for vehicle before, but because of its attenuation characteristic for lowfrequency, more and more questions were found during the noise evaluation, and thesubjective feelings of human were not reflected, therefore, the research of sound qualitywas risen in response to the proper time and conditions. The subjective feelings ofhuman taken by sound are researched in sound quality, which is the hot spot of NVHresearch for vehicle.A large number of domestic and foreign related researches are read, and themethod of combining objective numerical calculation and subjective evaluationexperiment is used, then the interior sound quality of vehicle under accelerated drivingcondition is intensive studied in this paper.Firstly, the time-varying models of each psychoacoustics objective parameter areestablished, on the basis of the steady model, the time-varying characteristics ofacceleration noise are considered, the time-varying algorithm of each objectiveparameter is designed by MATLAB, the dynamic characteristic of the acceleration noisecan be reflected compared to the steady algorithm model, and the accuracy of theobjective evaluation is improved.Secondly, the3560B data collection front-end and4101A binaural microphonemade in B&K company are used, the interior noises of14brands of vehicles duringacceleration from30km/h to80km/h, have been collected according to the “GB/T18697-2002the acoustic car interior noise measurement method” in this experiment.The main psychoacoustics objective parameters of the14different samples have beencalculated by the MATLAB designed in this paper, the loudness、sharpness、roughness、fluctuation and A-weighted SPL of noise samples can be gotten.After that, the subjective evaluation tests have been carried out on the14noisesamples by the paired comparison, and the misjudgment and unstable results areremoved, through correlation analysis and multivariate linear regression analysis, theevaluation models for vehicle interior noise under accelerated driving condition havebeen established. At last, the accuracy of evaluation model has been verified. Through the test ofregression coefficient and prediction of evaluation model, a better goodness-of-fit of themodel has been shown,it is effective and meaningful in statistics,and the interior soundquality of vehicle under accelerated driving condition can be better evaluated andpredict, the significant guide for acoustic design and vibration and noise reduction ofvehicle is provided.