程力学 33 4 结论 (1)对于含中心裂纹正交各向异性板,在远场 均匀热流作用下,针对两种新的温度边值问题,求 1.2 得了温度场的全场解析解。所获的解, 精确满足 as 给定的全部边界条件。 2)研究表明,对于所给定的两种温度边值间 题,温度梯度场具有r2的奇异性,而温度场本身 没有奇异性。裂纹表面上的边界条件 对于温度场 420 2468 的性质与分布起着决定作用。裂纹的传热能力,对 图11边界条件;=8,=下裂纹的温度等值线 于温度场的性质与分布有重要影响。 3=50K/m(导热裂纹,6=200K/m,5=400Km (3)第一种边界条件下,即裂纹上、下表面沿 Fig.I1 Temperature isoclines near the crack under the 裂纹方向无温度梯度时,产生正对称分布的温度 boundary condition==with=50K/m 场。 (Uninsulated crack).=200K/m and =400K/m (4)对于第二种边界条件,即裂纹的上、下表 面沿垂直裂纹方向维持一恒定的温度梯度时,裂纹 的上、下表面将具有不同的温度。当从左到右跨越 裂纹的垂直对称轴时,温度发生跳跃。这一现象, 有待于进一步深入进行理论探讨与实验验证。 参考文献: [1]Boley B A,Weiner J H.Theory of thermal stresses [M] Wiley,New York,1960. 2]Sih GC.Heat conducti in the infinite 图12边界条件;==下裂纹附近的温度等值线 6=50K/m(得热裂纹.g=300K/m,85=300K/m 3]Sih GC.On the singular character of thermal stress Fig.12T a crack tip Joural of Applied Mechanics,192.29 dary condition with=50K/m 587-589 (Uninsulated crack)K/m and0/ em I of .1960.27:635-639 [5]Tzou DY.Strain energy density-a molecular ap Joumal of the Chinese Institute of Engineers,2004 76):919-929 Mindlin R D.Equa of solids and Stuctures 1974.10:625-637 7]Nowacki W.Some general theorems of thermopiez electricity []Journal of Thermal Stresses,1978.1: 71-18 8 20 图13边界条件⊙时=⊙=⊙下裂纹附近的温度等值线 713949. g=50Km(得热裂纹,=400Km,6=200Km Fig.13 Temperature isoclines near the crack under the (参考文献9小16转第41页) boundary conditionwith50K/m (Uninsulated crack).=400K/m and=200K/m 1994-2015 China Academic Joural Electronie Publishing House.All rights reserved http://www.cnki.net 工 程 力 学 33 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 -10 -8 -6 -4 -2 0 2 4 6 8 10 x1/a 0.8 1 1.1 0.9 1 0.9 0.8 0.7 1.1 1.2 x1/a x2 / a Θ /Θ0 =1.3 Θ /Θ0 =0.7 a =10mm, k11=50W/km, k22=75W/km + Θ,2 = − Θ,2 = 0 Θ,2 =50K/m, * Θ0 =100K, ∞ Θ,1 =200K/m, ∞ Θ,2 =400K/m * * 图 11 边界条件 0 Θ,2 ,2 ,2 Θ Θ + − = = 下裂纹的温度等值线: 0 ,2 Θ = 50K/m (导热裂纹), ,1 Θ 200K/m ∞ = , ,2 Θ 400K/m ∞ = Fig.11 Temperature isoclines near the crack under the boundary condition 0 Θ,2 ,2 ,2 Θ Θ + − = = with 0 ,2 Θ = 50K/m (Uninsulated crack), ,1 Θ 200K/m ∞ = and ,2 Θ 400K/m ∞ = -10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 -10 -8 -6 -4 -2 0 2 4 6 8 10 x1/a 0.8 1 0.9 1 0.9 0.8 1.1 1.2 x1/a x2 / a Θ /Θ0 =1.3 Θ /Θ0 =0.7 a =10mm, k11=50W/km, k22=75W/km + Θ,2 = − Θ,2 = 0 Θ,2 =50K/m, * Θ0 =100K, ∞ Θ,1 =300K/m, ∞ Θ,2 =300K/m * * 图 12 边界条件 0 Θ,2 ,2 ,2 Θ Θ + − = = 下裂纹附近的温度等值线: 0 ,2 Θ = 50K/m (导热裂纹), ,1 Θ 300K/m ∞ = , ,2 Θ 300K/m ∞ = Fig.12 Temperature isoclines near the crack under the boundary condition 0 Θ,2 ,2 ,2 Θ Θ + − = = with 0 ,2 Θ = 50K/m (Uninsulated crack), ,1 Θ 300K/m ∞ = and ,2 Θ 300K/m ∞ = -10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 -10 -8 -6 -4 -2 0 2 4 6 8 10 x1/a 0.9 1 0.9 0.8 1.1 1.2 x1/a x2 / a Θ /Θ0 =1.3 a =10mm, k11=50W/km, k22=75W/km + Θ,2 = − Θ,2 = 0 Θ,2 =50K/m, * Θ0 =100K, ∞ Θ,1 =400K/m, ∞ Θ,2 =200K/m * 图 13 边界条件 0 Θ,2 ,2 ,2 Θ Θ + − = = 下裂纹附近的温度等值线: 0 ,2 Θ = 50K/m (导热裂纹), ,1 Θ 400K/m ∞ = , ,2 Θ 200K/m ∞ = Fig.13 Temperature isoclines near the crack under the boundary condition 0 Θ,2 ,2 ,2 Θ Θ + − = = with 0 ,2 Θ = 50K/m (Uninsulated crack), ,1 Θ 400K/m ∞ = and ,2 Θ 200K/m ∞ = 4 结论 (1) 对于含中心裂纹正交各向异性板,在远场 均匀热流作用下,针对两种新的温度边值问题,求 得了温度场的全场解析解。所获得的解,精确满足 给定的全部边界条件。 (2) 研究表明,对于所给定的两种温度边值问 题,温度梯度场具有 r -1/2 的奇异性,而温度场本身 没有奇异性。裂纹表面上的边界条件,对于温度场 的性质与分布起着决定作用。裂纹的传热能力,对 于温度场的性质与分布有重要影响。 (3) 第一种边界条件下,即裂纹上、下表面沿 裂纹方向无温度梯度时,产生正对称分布的温度 场。 (4) 对于第二种边界条件,即裂纹的上、下表 面沿垂直裂纹方向维持一恒定的温度梯度时,裂纹 的上、下表面将具有不同的温度。当从左到右跨越 裂纹的垂直对称轴时,温度发生跳跃。这一现象, 有待于进一步深入进行理论探讨与实验验证。 参考文献: [1] Boley B A, Weiner J H. Theory of thermal stresses [M]. Wiley, New York, 1960. [2] Sih G C. Heat conduction in the infinite medium with lines of discontinuities [J]. J. Heat Transfer, 1965, 87: 293~298. [3] Sih G C. On the singular character of thermal stresses near a crack tip [J]. Journal of Applied Mechanics, 1962, 29: 587~589. [4] Florence A L, Goodier J N. Thermal stresses due to disturbance of uniform heat flow by an insulated ovaloid hole [J]. J. of Applied Mechanics, 1960, 27: 635~639. [5] Tzou D Y. Strain energy density – a molecular appraisal [J]. Journal of the Chinese Institute of Engineers, 2004, 27(6): 919~926. [6] Mindlin R D. Equations of high frequency vibrations of thermopiezoelectric crystal plates [J]. International Journal of Solids and Structures, 1974, 10: 625~637. [7] Nowacki W. Some general theorems of thermopiezoelectricity [J]. Journal of Thermal Stresses, 1978, 1: 171~182. [8] Chandrasekharaiah D S. A generalized linear thermoelasticity theory for piezoelectric media [J]. Acta Mech., 1988, 71: 39~49. (参考文献[9]~[16]转第 41 页)