Simulation on antishock performance of a marine diesel engine by using finite element calculation based on multibody dynamics

Various shock waves in time domain were translated into shock response spectrums(SRS).It was found that the peak acceleration value of 10ms triangular shock wave is equal to the acceleration value on the isoline of SRS.Accordingly,10ms triangular shock wave was suggested as the standard input load for anti-shock performance analysis of equipment.By virtue of the software of ABAQUS6.7,the flexible multi-body and anti-shock analysis model of the whole engine,including the backbone,was established.The shock simulations of a V6 type diesel were carried out under rated condition and standing condition respectively.The simulation results indicate that the shock response characteristic of diesel engine is nonlinear.The stress response under rated condition added with a shock is not the simple superposition of the shock stress under standing condition plus the working stress under rated condition.The strength of crankshaft,cylinder block,flywheel housing and block support should be checked through shock simulation.