Design and Analysis of Crankshaft Used in Aerospace Applications and Comparision Using Different Materials

The overall objective of this project was to evaluate and compare the fatigue performance of two competing manufacturing technologies for aerospace crankshafts, namely forged steel and ductile cast iron. In this project a dynamic simulation was conducted on two crankshafts, forged steel and ductile cast iron, from similar four cylinder four stroke engines. Finite element analysis was performed to obtain the variation of stress magnitude at critical locations. The pressure-volume diagram was used to calculate the load boundary condition in dynamic simulation model, and other simulation inputs were taken from the engine specification chart. The dynamic analysis was done analytically and was verified by simulations in ANSYS. Results achieved from aforementioned analysis were used in optimization of the forged steel crankshaft. Geometry, material, and manufacturing processes were optimized considering different constraints, manufacturing feasibility, and cost. The optimization Process included geometry changes compatible with the current engine, fillet rolling, and the use of micro alloyed steel, resulting in increased fatigue strength and reduced cost of the crankshaft, without changing connecting rod and or engine block.