A study on the fillet stress calculation of crankshaft in a highly-intensified diesel engine

By comparing the simplified model for stepped shaft with the model for a single crank of crankshaft, and applying the convergence criteria of the simplified model for stepped shaft to the model for single crank, a crankshaft FE model with good convergency and stability is built. Based on an analysis on the stress distribution in the fillet region of that model, a method is proposed of using first-order Fourier series and low-order polynomials to fit the stress distribution of fillet region along different directions with good results and strong correlation between stress distribution expression and the data of FE calculation.