Dynamic Structural and Modal Analysis of Camshaft Using Finite Element Analysis with Material Optimization

Abstract

This study presents a comprehensive finite element analysis (FEA) of a 4-cylinder compression ignition (CI) engine camshaft based on the TATA Safari Dicor geometry and material data, to evaluate and optimize material selection for superior structural and dynamic performance. Four candidate materials were investigated: grey cast iron and aluminium-silicon carbide (AlSiC) metal matrix composites with 20%, 30%, and 40% SiC reinforcement. The camshaft geometry was modelled in SolidWorks 2023 and analysed in ANSYS Workbench 2023 R1 using Tet10 elements under static structural, pre-stressed modal, and harmonic response analyses. A fixed support at each journal and a concentrated force of 5000 N at the cam nose were applied as boundary conditions. Static analysis revealed maximum von Mises stresses of 21.291 MPa (cast iron), 20.993 MPa (AlSiC 20%), and 21.017 MPa (AlSiC 30% and 40%), all well below respective tensile limits. AlSiC 40% achieved the minimum total deformation of 0.0031311 mm, a 21.0% improvement over cast iron (0.003965 mm). Modal analysis yielded first natural frequencies of 8,725.4 Hz (cast iron), 13,598 Hz (AlSiC 20%), 14,626 Hz (AlSiC 30%), and 15,769 Hz (AlSiC 40%), all providing frequency separation ratios of 87–158 relative to the maximum engine excitation frequency of ~100 Hz. The theoretical frequency ratio from specific stiffness (√(49.82/15.28) = 1.806) matches the computed ratio (1.807) to within 0.06%, confirming simulation validity. Harmonic response analysis confirmed resonance peaks far beyond the operational frequency range for all materials. AlSiC 40% additionally delivers 60.8% weight reduction versus cast iron. These results establish AlSiC 40% as the optimal material, extending the findings of Patra et al., dynamic performance when harmonic response and pre-stressed modal analyses are incorporated into the assessment.