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272 摩 擦 学 学 报 第 41 卷
啮合齿面间的摩擦系数为 解方法,得到热弹流润滑状态下双渐开线齿轮传动啮
∫
x out 合齿面摩擦系数分布情况,如图4(a)所示. 由图4(a)可
µ= τdx/w (14)
知,啮入端与啮出端的摩擦系数较大,齿腰分阶附近
x in
1.4 啮合齿面摩擦系数分布 的摩擦系数较小. 因为齿腰分阶位置的滑滚比与相对
双渐开线齿轮传动系统相关参数列于表1中,啮 滑动速度较小,接触副近似于纯滚动. 与啮出端相比,
合齿面间润滑油性能参数列于表2中. 啮入端的滑滚比和相对滑动速度较大,等效曲率半径
啮合齿面间的摩擦系数与齿轮温度场密切相关 [24-25] . 和卷吸速度较小,使其油膜厚度较小,如图4(b~c)所
根据表1、表2及文献[26]中的热弹流润滑控制方程求 示,导致啮入端的摩擦系数高于啮出端.
表 1 双渐开线齿轮系统参数
Table 1 Parameters of double involute gear system
Number of teeth Normal modulus/mm Normal pressure angle/(°) Helix angle/(°) Tooth width/mm Thermalconductivity/[W/(m·K)]
23/32 m n =3 a n =20 β=16°57′42″ β=50 k a =k b =46
3
Poisson’s ratio Specific heat capacity/[J/(kg·K)] Modulus of elasticity/GPa Density/(kg/m ) Speed/(r/min) Torque/(N·m)
υ=0.3 c a =c b =460 E a =E b =210 ρ a =ρ b =7 850 υ 1 =2 000 T p =160
表 2 润滑油性能参数
Table 2 Performance parameters of lubricating oil
2
Density/(kg/m ) 3 Kinematic viscosity/(m /s) Specific heat capacity/[J/(kg·K)] Thermal conductivity/[W/(m·K))
ρ f =870 v f =95.2×10 −6 c f =2 000 λ f =0.14
μ 0.051 80 Us 2.590 0
0.048 77 2.331 0
0.050 0.045 74 2.5 2.072 0
0.042 71 2.0 1.813 0
Friction coefficient 0.040 0.033 62 Friction coefficient 1.5 1.036 0
0.045
1.554 0
0.039 68
1.295 0
0.036 65
0.777 0
0.030 59
0.035
0.518 0
0.027 56
1.0
0.030
0.259 0
0.024 53
0.025
Contact line position/mm Meshing cycle/(t/T c ) 0.5 0.0 0
0.020 40 50 0.021 50 0.5 40 50 0.000 0
0.0
2.5 20 30 20 30
2.0 1.5 10
10
1.0 2.5 2.0 Contact line position/mm
1.5
0
0.5
1.0
0.0
Meshing cycle/(t/T c )
(a) Friction coefficient (b) Relative sliding velocity
h 0.610 0
0.588 5
0.60 0.567 0
Friction coefficient 0.055 0.502 5
0.545 5
0.524 0
0.481 0
0.050
0.459 5
0.438 0
0.045
0.395 0
0.040 50 0.416 5
2.5 30 40
2.0 1.5 20
1.0 10
0.5 Contact line position/mm
0.0 0
Meshing cycle/(t/T c )
(c) Oil film thickness
Fig. 4 Distribution of friction coefficient and oil film thickness( l = y = 0.05)
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图 4 齿面摩擦系数、相对滑动速度与油膜厚度分布( l = y = 0.05)
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