【摘要】 为提高高温气冷堆中间换热器的换热效率,对中间换热器单元流道的湍流边界层分布及其传热特性进行了理论计算和不同湍流模型的模拟分析,得到了适用于中间换热器高温高压单元流道的湍流模型。根据不同模型的边界层分布以及中心区流体速度和温度的变化情况,发现在单元流道内流体边界层区和Poiseuille流动区的相关特征及分界点。同时,验证了3种湍流模型在Nu-Re数关系及壁面局部摩擦阻力2种情况下,与理论公式解的吻合情况,为下一步增加人为粗糙度的强化传热研究提供了理论支持。更多还原

【Abstract】 The flow in the intermediate heat exchanger(IHX)of a high temperature gas-cooled reactor was simulated using various turbulence models to study the turbulent boundary layer in the IHX to improve the thermal efficiency of the high temperature,high pressure IHX.The boundary layer distributions predicted by the models and the velocity and temperature changes in the central region were used to characterize the boundary layer area and the Poiseuille flow area.The results also verify the three kinds of turbulence models and an analytical solution,including the relationship between Nu and Re and the partial wall friction resistance.These results provide theoretical support for heat transfer enhancement using artificial roughness elements.更多还原