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针对某涡轮导向叶片,实验测量了光滑叶片表面的压力系数和速比系数,并使用瞬态液晶测量技术获得了叶片全表面传热系数分布.分别使用shear stress transport(SST),k-ω,k-ε和renormalization group(RNG)k-ε四种湍流模型模拟了相同结构尺寸的叶栅通道内的流动与换热,并与实验结果进行对比.结果表明:压力面压力系数沿弧长方向逐渐下降,吸力面上压力系数先快速下降达到最小值后缓慢上升(出现逆压梯度).叶栅通道和叶片表面附近气流流动结构的复杂性导致叶片表面传热系数分布较为复杂.4种湍流模型对压力系数和速比系数的计算结果相互差别不大,计算数据也比较接近实验值.关于叶片表面传热系数,SST模型计算结果分布规律与实验接近,而其他3种湍流模型都没有能模拟出吸力面边界层分离对换热的影响.
For a turbine guide vane, the pressure coefficient and speed ratio coefficient of the smooth blade surface were measured experimentally, and the whole surface heat transfer coefficient distribution of the blade was obtained by using the transient liquid crystal measurement technique.The shear stress transport (SST), k-ω, k-ε and renormalization group (RNG) k-ε were used to simulate the flow and heat transfer in the cascade passage of the same structure size and compared with the experimental results.The results show that the pressure coefficient of pressure surface along the arc length direction The pressure coefficient on the suction surface decreases rapidly and reaches the minimum and then increases slowly (the reverse pressure gradient appears) .The complexity of the airflow structure near the blade passage and the blade surface leads to a more complicated distribution of the heat transfer coefficient on the blade surface.The four kinds of turbulence The calculated results of pressure coefficient and speed ratio are not different from each other, and the calculated data are also close to the experimental value.As for the heat transfer coefficient of leaf surface, the distribution of SST model is close to the experiment, while the other three kinds of turbulence model The effect of boundary layer separation on heat transfer was simulated.