Study On The Method Of Inverse-substructuring Transfer Path Analysis And Its Engineering Application

Transfer path analysis(TPA),as an effective technique to solve the problem of vehicle noise and vibration,and improve the performance of NVH,has been developed in a wide range of engineering applications.Traditional TPA,OPA,OPAX,fast TPA,multi-level TPA,hybrid TPA and time domain TPA,each have their own advantages and applications,but also faced with the contradiction between the accuracy and workload.Working load identification and non-coupling FRF measurement is the most timeconsuming work TPA.The inverse-substructuring analysis method was introduced into TPA,to make full use of the advantage of the method,which can obtain the dynamic parameters of interface between substructures and the dynamic characteristic of substructures without decoupling the system,to have the dynamic stiffness of interface and non-coupling FRF of substructure,and then identify the working condition load through dynamic stiffness method and analysis the path contribution.In this process,it is not necessary to decouple the system and do not need to test the dynamic stiffness of the interface,so as to improve the working efficiency.In this paper the basic principle of inversesubstructuring TPA was elaborated in detail,and simulation analysis was carried out by using lumped parameter model to verify the validity of the method.Based on inverse-substructuring TPA method an analysis model and a data acquisition process for engineering application were established,and applied to a certain type of vehicle cab vibration transfer path analysis.The cab vibration level test,working condition data acquisition and FRF test of the prototype were carried out,and calculated the dynamic stiffness of powertrain mounts and non-coupling FRF of the cab,and then realized the load identification and path contribution analysis.Successfully find out the biggest load and the maximum response contribution path of each target point,and pointed out the direction for further improvement and optimization,has also proved the feasibility of inverse-substructuring TPA for engineering application.