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在指尖密封多孔介质流动模型的基础上,将指尖密封片之间的接触传热附加于固体导热之中,之后通过对密封固体结构与结构内流体的耦合各向异性传热进行理论分析,建立了指尖密封各向异性传热数学模型;基于商业软件Fluent中的用户自定义标量(UDS)方程功能,开发了多孔介质各向异性传热数值计算模块,并数值模拟了指尖密封结构内的流动与传热特性。结果表明:指梁与指尖靴区域的各向异性有效导热系数张量与孔隙率、径向和周向位置以及轴向接触热阻等因素相关;指尖密封最高温度出现在指尖靴与转子接触面的略下游处;与各向同性传热模型相比,采用各向异性传热模型时,指梁下部和指尖靴区域沿径向和轴向存在较大温度梯度,但温度沿周向的变化两者均很小;泄漏量随着压差的增加逐渐增大,随着转子转速的增加基本不变;指尖密封最高温度值随着压差的增加逐渐减小,随着转子转速的增加逐渐增大。
Based on the fingertip porous media flow model, the contact heat transfer between fingertip seal is added to the thermal conductivity of the solid, and then theoretical analysis is conducted by the anisotropic heat transfer between the sealed solid structure and the fluid in the structure , A mathematical model of fingertip seal anisotropic heat transfer was established. Based on the function of user-defined scalar (UDS) equation in commercial software Fluent, an anisotropic heat transfer numerical calculation module for porous media was developed and the fingertip seal Flow and heat transfer characteristics within the structure. The results show that the effective anisotropy of the thermal conductivity tensor of finger and finger tip boots is related to the porosity, radial and circumferential position and axial contact resistance. The maximum temperature of fingertip seal appears between fingertip boots and Rotor contact surface slightly downstream; Compared with the isotropic heat transfer model, the use of anisotropic heat transfer model, the lower part of the finger and fingertip boot region along the radial and axial greater temperature gradient, but the temperature along The circumferential variation is very small. The leakage increases with the increase of differential pressure and keeps unchanged with the increase of rotor speed. The maximum temperature of finger seal decreases with the increase of differential pressure. With the increase of differential pressure, Rotor speed increases gradually increased.