The Dynamic Simulation And Torsional Vibration Analysis Of Diesel Engine Based On Virtual Prototype Technology

Diesel is the basic power device of car,locomotive,tractor,construction machinery,ships, etc. Since the twentieth century, the fifties, along with the rapid development of science and the increasing of devices powered by internal combustion engines,people have more and more demindings on the improving of diesel.The performance of main parts of engine directly affects the reliability and life of the engine.With the continuous improving of strength norm, the working conditions of the working parts become more complex.Under a variety of Cyclical changing loads.the key issue is how to ensure that the parts of the engine can have sufficient fatigue strength,stiffness,dynamic properties and static mechanical properties during the designing of diesel engine. As the most critical components of diesel,how to ensure the safe and stability of the crankshaft is always the point of diesel engine research. This paper aims to explore a more precise way to analysis the dynamic response of the crankshaft.This paper selects a 16-cylinder diesel as research object and builds the virtual prototype of the diesel using software ADAMS and ANSYS(including the full rigid body model and two rigid flexible coupling models).The comparative study of the loading curve of the crankshaft journals and crank pins of the three models can prove that the flexibility of the crankshaft and block causes great influence. Further this paper studys the torsional vibration characteristics of the crankshaft. The rigid flexible coupling dynamic model of the engine is used to calculate the vibration angle curve changing with time and the harmonic analysis is done.The conclusion is that the first torsional vibration frequency is so high that only the frequency of high-order harmonic can approach it.The torsional vibration amplitude of the working condition cann't effect the safety of the diesel.Through the work mentioned before and its results it can be seen that virtual prototyping technology can really be convenient and accurate to predict the dynamic performance of the actual engine. It can save development costs, improve efficiency and enhance product performance during the engine designing.