EMPIRICAL RELATION TO ESTIMATE THE REDUCTION OF ROOT FILLET STRESS IN SPUR GEAR DUE TO ELLIPTICAL STRESS RELIEF FEATURES

Abstract

This work is an attempt to establish the empirical relations to predict the percentage of reduction of the root fillet stress in a spur gear due to elliptical stress relief features (SRF). To modify the stress field in a spur gear to reduce the stress concentration using elliptical stress relief feature has added advantage over the circular stress relief features, because it has more parameters such as major diameter, ratio of major to minor diameter and orientation of its axis to regulate stress field. An investigation on roo t fillet stress is in a spur gear with an elliptical stress relieving feature is carried out using finite element method. Based on the finite element analysis carried out nine empirical relations are proposed. With these relations it is possible to predict the percentage of reduction of root fillet stress in spur gear within 2percentages of deviation.