Crankshaft Dynamic Strength Analysis for Marine Diesel Engine

Dynamic strength analysis of crankshaft for two-stroke marine diesel engine is carried out on the normal operation. The finite element models of crankshaft, bearing, piston and connecting rod are created in ANSYS and simplified by sub-structure technique. The result files of reduced models are introduced into EXCITE software to create the multi-body dynamic model of marine diesel engine. The model is used for multi-body dynamics calculation of crankshaft in one working cycle. Then, the results are recovered to the fine solid finite element model of crankshaft to complete dynamic stress calculation. Compared with single crankshaft strength analysis, nonlinear multi-body dynamics method is closer to the actual boundary conditions of the crankshaft load, and this method may improve the dynamic characteristics calculation precision of marine diesel engine crankshaft.