预旋进气小尺寸涡轮叶片冷却的流动换热

为了获得一种具有直通式冷气预旋进气系统的小型燃气轮机涡轮叶片的流动与换热特性,采用气热耦合计算方法进行数值研究,分析了总压损失、冷却效果和涡轮效率随预旋角、冷气雷诺数和无量纲质量流量的变化规律。结果表明,涡轮叶片预旋进气冷却的总压损失随冷气雷诺数和无量纲质量流量的增大而增大,但基本不受预旋角大小的影响;涡轮叶片的冷却效果随预旋角的减小、冷气雷诺数或无量纲质量流量的增大而增强,但不会改变其表面的温度分布特征;预旋进气冷却时的涡轮效率随冷气雷诺数的增大、预旋角或无量纲质量流量的减小而提高。

Numerical Study on the Pre-Swirl Flow and Heat Transfer Characteristicsof a Small Gas Turbine Blade

Numerical study of flow and heat transfer characteristics in a rotating cascade of a small gas turbine,which adopted direct-transfer pre-swirl cooling system,was conducted by using ANSYS CFX 12.0.The effects of pre-swirl angle,cooling air Reynolds number and non-dimensional mass flow rate on the total pressure loss,cooling effectiveness and turbine efficiency were analyzed.The results show that total pressure losses of pre-swirl system and temperature distributions on blade are nearly same under various pre-swirl angles.Both cooling efficiency of blade and turbine efficiency increase with the diminishing of pre-swirl angle and non-dimensional mass flow rate or increasing of cooling air Reynolds number.