Dynamic Characteristics Analysis of Abnormal Vibration for Power Assembly of Diesel Engine of SUV

Abstract

With regard to the problem of abnormal vibration for power assembly of diesel engine of the Sport Utility Vehicle in working rotation speed conditions, the method of test mode combined finite element simulation analysis was adopted, the dynamic characteristics of the power assembly were studied in all conditions. First vibration modal testing of the power assembly was carried out in whole vehicle condition and in test bed, the cause of abnormal vibration of the power assembly was found out, the bending stiffness was low, then a kind of actual finite element simulation model of the power assembly was set up, the constraint mode was calculated. The rationality of finite element simulation model of the power assembly was validated. Integrated modal testing and simulation analysis showed that the low stiffness of flywheel shell led to the low first modal frequency of power assembly which was easily in the excitation frequency range of diesel engine working rotational speed, and resulted in system resonance of the power assembly