A novel thermal network model for predicting the contact temperature of spur gears

Abstract

This paper proposes a thermal network model to predict the contact temperature of spur gears. A crucial parameter in gear scuffing evaluation is the contact temperature, which comprises the bulk and flash temperatures. Herein, thermal network models of gear bulk temperature and flash temperature are established, by dispersing tooth into multiple temperature elements connected by the thermal resistances of heat conduction and heat convection. The thermal network model of gear bulk temperature is verified by the finite element model and previous work, and the presented model for gear flash temperature is validated by Blok flash temperature formula. Following ISO standard, gear scuffing is evaluated by comparing the contact temperature with scuffing critical temperature. The effects of geometric and operating parameters on the gear temperature are subsequently investigated. Contact temperature is found to decrease with increased tooth width, pressure angle and module, but increases with increased rotational velocity and input torque. These findings indicate that reasonable geometric and operating parameter matching are beneficial for increasing gear-scuffing resistance.