Modelling and simulation of a connecting rod of an internal combustion engine using finite element method

Abstract

The connecting rod is one of the most important moving components in an internal combustion engine. It is the link between the piston and the crankshaft. Its primary function is to transmit the push and pull from the piston pin to the crankpin by so doing converting the reciprocating motion of the piston to rotary motion of the crankshaft. The main objective of this research was to design a connecting rod of an internal combustion engine for improvement in weight and cost reduction. The connecting rod was modelled using Autodesk Inventor 2017 software. The modelled connecting rod was then imported into Ansys for further analysis. Static structural and modal analysis were carried out on the connecting rod of the four different materials namely: structural steel, titanium alloy, grey cast iron and aluminium 7075 T6 alloy to determine the total deformation, directional deformation, equivalent elastic strain, equivalent Von Mises stress, maximum principal stress, minimum principal stress and the safety factor. It was found that Al 7075 T6 connecting rod has the highest deformation of 0.62979 mm representing36 % which was more than all the other connecting rods. Structural steel connecting rod was found to have the lowest deformation of 0.22733 mm representing 13%. Titanium alloy and Al 7075 T6 connecting rods were found to have the lowest Von Mises stress of 372.51 MPa and 375.52 MPa respectively. It was also found that the induced stresses in all the connecting rods were lower than the yield strengths of the materials. Al 7075 T6, Titanium alloy and structural steel connecting rods were found to have their maximum factorof safetyvalues of 15 which is good for the design. The weights of all the connecting rods for the four materials were compared and it was found that Al 7075 T6 connecting rod was lighter in weight than the remaining connecting rods.