Based on the theory of heat conduction and tribology

the mathematical model of friction heat of meshing tooth surface with the combination of elastohydrodynamic lubrication and boundary lubrication and the calculation method of transient temperature field under the condition of starved lubrication were established. The distribution of transient temperature field and the temperature time curve were given

and the influences of power and rotational speed on transient temperature field were analyzed. Results showed that in the 5 min process of starved lubrication

the maximum temperature of the driving wheel increased by 657 ℃ when the power increased from 866 kW to 2 000 kW

and decreased by 8502 ℃ when the rotating speed increased from 5 000 r/min to 20 000 r/min. The results lay a foundation for the optimal clearance design of spiral bevel gear in helicopter main reducer under the condition of oil-free lubrication.