In this article, a coupling model of shafting torsional vibration with advanced injection angle is proposed to study the effect of advanced injection angle on shaft torsional vibration. Using Simulink, a model shaft system of a 4190ZL_C medium-speed diesel engine is created to study the effect. The proposed coupling model, the traditional simulation method and the test are conducted on the torsional vibration of the 4190ZL_C medium-speed diesel engine, separately. The results show that the spectrum from the coupling vibration model is more abundant than from the traditional vibration model. Hence, considering the effect of advanced injection angle on shaft torsional vibration, the proposed coupling model can improve the modeling accuracy of shaft torsional vibration. It provides a new approach in engine design.

In this paper, the coupling effect between the crankshaft torsional vibration and the low speed diesel engine block vibration is investigated. Using finite element method (FEM), a model of low speed diesel engine is established to study the vibration response. The mode results of FEM agree very well with the test. The additional torques acting on the low-speed diesel engine caused by torsional vibration are discussed in detail. The vibration response of the low-speed diesel engine considering the effect of torsional vibration is studied using FEM simulation. By analyzing the effect of torsional vibration, the results demonstrate that the crankshaft torsional vibrations have important effects on the engine block vibration. The results from this study can provide useful theoretical guidance to predict vibration of low-speed diesel engine.