Investigation on dynamic contact stress of the gear system with structure-thermal coupling field

In the case of high speed and heavy load, the operation of gear system is often accompanied by higher temperature. Therefore, the influence of temperature on contact stress cannot be ignored. The dynamic contact stress with thermal-structural coupling exists widely in the gear system. The concept of structural-thermal stress difference is put forward, and the reason of structural -thermal stress difference in gear system is explained theoretically. The theoretical calculation method of structural-thermal stress difference is deduced, and the dynamic contact stress of the gear system under different working conditions is analyzed by finite element method. The instantaneous temperature rise of each point on the tooth surface is calculated, and the correlation between temperature and dynamic thermal contact stress is revealed. The dynamic thermal contact stress and structural contact stress of single tooth meshing zone and double tooth meshing zone under various loads are studied, and the influence rules of different loads on dynamic thermal contact stress are summarized. The analysis of the gear models with different friction coefficients is carried out, and the effect of friction coefficients on structural-thermal stress difference of gears under different loads is revealed. Through the study of the gear systems with different rotational speeds, it is found that the main influencing factors of stress are loads. Finally, the reliability of the finite element method is testified by experiments.