Intelligent Time-frequency Optimization Design for Closure Parts of Transportation Vehicle
The semi-free acoustic field measurement under passenger vehicle door slamming condition needs to be carried out only after the whole vehicle manufacturing completion;therefore,it is crucial to predict and optimize the acoustic radiation of door slamming in advance.First,the acceleration vibration response and frequency response functions were obtained by designing vehicle experiments and bench experiments to achieve the discretization of transient impact loads under door slamming condition.Furthermore,the TPA-CWT method was proposed by combining transfer path analysis(TPA)and continuous wavelet transform(CWT)to perform discretized transient impact load time-frequency analysis.Second,according to the vehicle door dynamic characteristics under slamming condition,the discretized transient impact load was input into the established finite element model of door.Then,the door finite element transient acceleration vibration response was mapped to the body time domain boundary element model to predict the semi-free acoustic field radiation noise,and was compared with the actual measured results at the microphone in vehicle experiment.The overall trend and local peak value of sound pressure curve proved that the time domain boundary element simulation could accurately capture the transient sound pressure characteristics under door slamming condition.Finally,the components with top three low-frequency noise contributions were selected as design variables through equivalent radiated power.The multi-objective particle swarm optimization was then used to optimize the door mass and door slamming acoustic radiation.The door mass was reduced by 1.8％after optimization,and the door slamming acoustic radiation was reduced by 1.7％,achieving the purpose of multi-objective optimization.The result indicates that the simulation data are in good agreement with the experimental results,verifying the feasibility of multi-objective optimization under door slamming conditions through discretization of door slamming transient load and sound-solid coupling analysis.It also provides certain guidance for the door design of subsequent facelift models.
outomotive engineeringsemi-free acoustic fieldtransfer path analysisfinite element methodboundary element
NETL
NSTL
万方数据
