为了研究摩擦系数对燕尾形叶根-轮槽静强度的影响规律与机理，以某300 MW F级重型燃气轮机燕尾形叶根-轮槽模拟件为研究对象，针对摩擦系数取值0~1的范围开展了有限元数值模拟，分析了等效应力、法向接触力、切向接触力、滑移量等参数的变化规律及变化原因。结果表明：燕尾形叶根-轮槽最大等效应力随着摩擦系数的增大而先减小后增大，说明设计与安装时接触面摩擦系数的选取并不是一定越小越好；摩擦系数从0.1增大到0.5，燕尾形叶根-轮槽最大等效应力增大30.45%，可见燃机运行中接触面摩擦系数的增大对叶根-轮槽危害较大；当摩擦系数小于0.5时，摩擦系数的影响较大，当摩擦系数大于0.5时，由于接触面摩擦状态由滑移逐渐变为粘着，摩擦系数的影响逐渐减弱；摩擦系数对燕尾形叶根-轮槽静强度的影响通过接触面上法向接触力、切向接触力、摩擦状态的共同作用来实现，齿面所有位置的等效应力峰值随着法向接触力减小而减小，倒角等效应力峰值及其邻近接触面边缘的等效应力峰值随着切向接触力的增大而增大。

In order to investigate the influence patterns and mechanisms of friction coefficient on static strength of dovetail root and groove, finite element numerical simulations were conducted on the specimen of dovetail root and groove in a 300 MW F-class heavy-duty gas turbine, considering a friction coefficient range of 0 to 1. The variations and reasons of parameters such as equivalent stress, normal contact force, tangential contact force, and slip distance were analyzed. The results show that the maximum equivalent stress of dovetail root and groove initially decreases and then increases with the increase of friction coefficient, which indicates that the selection of friction coefficient on contact surface during design and installation is not necessarily better with smaller values; when the friction coefficient increases from 0.1 to 0.5, the maximum equivalent stress of dovetail root and groove increases by 30.45%, which indicates that the increase in friction coefficient on contact surface during the operation of gas turbine is detrimental to the structural safety of root and groove; when the friction coefficient is less than 0.5, its influence is significant, but when the friction coefficient exceeds 0.5, due to the transition of friction state on contact surface from sliding to sticking, the influence of friction coefficient is gradually weakened; and the effect of friction coefficient on structural strength of dovetail root and groove is achieved through the combined effects of normal contact force, tangential contact force, and friction state, the peak equivalent stress at all positions on tooth surface decreases with the decrease in normal contact force, while the peak equivalent stress at chamfers and adjacent edges of contact surface increases with the increase in tangential contact force.

国家科技重大专项资助（J2019-IV-0022-0090）