Design Optimization and Finite Element Analysis of a Six-Cylinder Heavy-Duty Crankshaft using Taguchi Method

The crankshaft is a critical component of an internal combustion engine that is continuously subjected to bending, torsional, and cyclic loading conditions. The structural integrity and dynamic performance of the crankshaft directly influence engine reliability, durability, and operational efficiency. In the present study, a six-cylinder heavy-duty crankshaft was modelled using Autodesk Inventor and analysed using ANSYS Workbench. Static structural and modal analyses were performed to evaluate equivalent stress, total deformation, elastic strain, safety factor, and vibration characteristics under operating conditions. A comparative assessment was carried out using Mild Steel (MS), EN19, EN24, and Titanium Alloy materials. Furthermore, Taguchi optimization was employed to identify the optimal geometric parameters for minimizing stress concentration and improving structural performance. The results indicate that EN19 and EN24 exhibit superior stiffness, lower deformation, and improved vibration resistance compared to the other selected materials. The Taguchi optimization analysis identified the optimal combination of crankpin diameter, main journal diameter, and fillet radius, resulting in enhanced structural reliability and load-bearing capability. The proposed methodology provides an effective approach for the design and optimization of heavy-duty crankshafts used in modern engine applications.