03.2020.224.234

DYNAMIC LOAD FACTOR FOR SINGLE ELEMENT CAMSHAFT UNDER HARMONIC EXCITATION

Author(s):
Nassear Rasheid Hmoad1, Aveen Ahmed Abdulkareem2 & Mohammad Qasim Abdullah3

Affiliation(s):
1University of Baghdad, College of Engineering, Aeronautical Eng. Dept

2University of Baghdad College of Engineering, Mechanical Eng. Dept

3University of Baghdad College of Engineering, Mechanical Eng. Dept

*Corresponding Author Email: nassear_machine@yahoo.com, av_mechanics@yahoo.com

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Due to its obvious role as a mechanical controller engaging most of mechanical applications, cam has been paid a lot of attention regarding its dynamic behavior. This work analyzes the induced static and dynamic forces associated to its work and evaluates its effective value by formulating the camshaft dynamic load factor to be used in static analysis of the camshaft dynamic performance. The instantaneous dynamic interaction force has been formulated according to Newton’s 2nd law to be used in evaluating the dynamic contact stress taking into account the damping ratio, the dynamic load factor and the wear rate concerning to Archared wear equation. Analytical results traced the induced static and dynamic contact forces as well as their resulted contact stresses at different points along the cam curvature and implied that the max. static and dynamic stresses take place at different positions which make it impossible to formulate the dynamic load factor to the cam itself. FEM has been used to evaluate the static contact stress value and distribution to be compared with that of Hertz equation to check the validity and it showed that the discrepancy percentage was about 3.8%.