Analysis For Strength And Experimental Study Of Marine Diesel Engine Crankshaft

As one of the most important components of diesel, crankshaft has been a vital part indiesel design and research, due to its geometric structure, boundary conditions andcomplexity of applied loads. Generally, static analysis and dynamic analysis by a variety ofways are conducted to study crankshaft. So the correct and reasonable analysis method isthe key approach to crankshaft study. During the strength check process of crankshaft, theinfluence of vibration and other shafting components in actual operation should beconsidered comprehensively.Firstly, static stress experiment on single-crank of a certain type of diesel is conductedto measure the tension-compression stress distribution of crankshaft at the top dead centerand bottom dead center position. Then finite element analysis of two different boundaryconditions corresponding to experimental load is analyzed and after comparative analysis,the more accurate boundary conditions of the diesel crankshaft is selected for static stressanalysis. Stress-strain distribution of crankshaft in each cylinder firing is got and on thisbasis, fatigue analysis is studied.Finally, the multi-body dynamics analysis software is used in diesel crankshaft analysisto get crank steady running and vibration in a complete operating cycle. And crankshaftstress distribution and change is gained by stress restore in one cycle, which is applied forfurther analysis of crankshaft fatigue and safety. In contrast to static stress analysis, resultsshow that in actual operation cylinder gas pressure has a significant impact on crankshaft, aswell as crankshaft natural frequency, dynamic response, torque changes, vibration in eachdirection, and torsional vibration. So it is necessary to take these factors into considerationin the process of crankshaft design and improvement.