Road load spectrum test analysis for engine flywheel cover

NIU Jian, YU Xiao-li, HUANG Rui, FENG Yan, CHEN Jun-xuan, LIU Zhen-tao, ZHOU Xun

（Institute of Power Machinery and Vehicular Engineering, Zhejiang University, Hangzhou 310027, China）

Abstract: As an important structure and support part of engine, flywheel cover is easily damaged. In order to obtaining the stress characteristics of flywheel cover, one kind of data acquisition system based on NI-DAQ was established to collect the stress spectrum of the dangerous parts in flywheel cover during two typical road condition including coarse grained and large structure and two kinds of load condition including full load and empty load. The correction of stress spectrum and the extraction of time-frequency feature were completed by using data processing platform based on C++, including plane stress analysis, amplitude spectrum analysis and waterfall analysis. The results indicate that flywheel cover works under uniaxial stress state, and the failure mechanism of flywheel cover is fatigue damage under the action of alternating stress. The main damage results from low frequency vibration below 80 Hz. The dominant vibration source is engine and the engine speed is the major effect factor. Comparison between various working conditions indicates that the damage mainly occurs in high roughness surface, full load condition and high engine speed condition.