气热耦合条件下涡轮动叶叶型与冷却结构优化

Conjugate Heat Transfer Optimization for Blade Profiles and Cooling Structure in Turbine Rotor

关键词:  气热耦合  冷却结构  动叶  优化  温度场  气动效率

Key words:  Conjugate heat transfer  Cooling structure  Rotor  Optimization  Temperature field  Aerodynamic efficiency

摘要:

为改善叶片表面温度场，提高叶片气动效率，对燃气涡轮动叶进行了针对叶型以及冷却结构的气热耦合优化。优化结果表明:对冷却结构以及叶型优化后，叶片表面最高温度降低13.64K，平均温度降低6.46K，尾缝冷气出口温度提升6.81K，尾缝出口马赫数由0.24增大至0.30，高温函数降低85.20% ，气动效率提高0.58%。通过分析，对该涡轮动叶，尾缘第三腔冷气流动速度的增大及第三腔叶顶冷气低速漩涡区的缩小是减小叶片表面温度的主要因素；型面压差减小导致横向二次流损失的降低及三个截面马赫数减小导致的激波损失降低是减小气动损失的主要因素。

Abstract:

To ameliorate the temperature distribution of blade and improve aerodynamic performance，conjugate heat transfer was taken to optimize the cooling structure and blade profiles. The results show that by conjugate heat transfer optimization on cooling structure and profile，maximum temperature of blade surface reduces 13.64K，while the average temperature of blade surface drops 6.46K，exit temperature of trailing edge raises 6.81K，while exit Mach number increases from 0.24 to 0.3，high temperature function decreases 85.20%，aerodynamic efficiency increases 0.58%.By the analysis of the turbine rotor blade，the increase of cooling flow velocity and the decrease of low speed vortex region in the third cavity of trailing edge are the main factors in lowing blade surface temperature. The low transverse secondary flow loss led by reducing of pressure difference between pressure surface and suction surface，and the low shock loss resulting from decrease of Mach number in three sections are the main factors in reducing the aerodynamic loss.