考虑冷气的多级涡轮翘曲S1流面的气动优化

为了缩短涡轮气动设计的周期,进一步发掘涡轮叶型的改进潜力,搭建了多级涡轮的翘曲S1流面气动优化平台.该平台具有速度快,周期短的特点.在考虑冷气的前提下,对多级叶片进行多层并行优化,避免了单列优化后叶列间匹配差的缺点,同时克服了多层S1流面的气动效率此消彼长的缺陷.对某型两级高压涡轮进行了气动优化设计,优化后10%,50%,90%叶高的S1流面的考虑冷气的气动效率分别提高了0.569%,0.490%,0.405%;第1级和第2级考虑冷气的气动效率分别提高了0.18%,0.05%;涡轮整体气动效率提高了0.15%;优化效果明显.经过分析可知,优化有效减小第1级导叶的通道横向二次流损失和第1级动叶的激波损失,第2级的原始叶型设计较为合理.下端壁喷射冷气是降低S1流面优化有效性的重要原因.

Aerodynamic optimization for twisted S1 stream surface of multi-stage turbine considering cooling air

To shorten the turbine aerodynamic design cycle and further explore the potential improvement of turbine blades, an aerodynamic optimization platform of twisted S₁ stream surface for multi-stage turbine with advantages of fast speed and short design period was presented. The platform could conduct multilayer parallel optimization for multi-column blades under the premise of cooling air, avoid disadvantage of poor matching between blade columns in single column optimization, and overcome the defect of aerodynamic efficiency shift for multilayer S₁ stream surface. A two stage high pressure turbine has been optimized; the results showed that, aerodynamic efficiency considering cooling air of three S₁ stream surfaces of 10%, 50%, 90% blade spanwise height was increased by 0.569%, 0.490% and 0.405%, the first stage and second stage aerodynamic efficiency considering cooling was improved by 0.18% and 0.05%, and aerodynamic efficiency considering cooling air of the turbine was increased by 0.15%, showing the significant effect of optimization. The analysis indicated that, the optimization reduced the channel transverse secondary flow loss of first stage stator blades and the shock loss of first stage rotor blades effectively, and the original blade design of turbine second stage was more reasonable. Coolant injection of flow channel hub was the important reason to reduce the effectiveness of S₁ stream surface optimization.