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该文重点讨论弯扭叶片设计方法在小展弦比的涡轴发动机涡轮叶片设计中的应用,旨在通过多方案的弯曲设计分析具有强二次流动的涡轮叶片的弯曲优化所能带来的气动性能改善和流场结构变化。给出了弯高固定而弯角不同的14个叶片弯曲设计方案。通过数值模拟计算分析了这些方案中总压比和流量,初步得出在该叶片设计中反弯设计要优于正弯和直叶片设计,且反弯15°方案为最优方案。根据密流沿叶高分布图分析了正弯、直和反弯叶片情况的下端区和中间区域的通流能力变化。结合叶片壁面极限流线图和静压分布,可发现反弯情况下造成的反向C型压力分布使得端区流动不但没有改善反而恶化,但是中间区域的低能流体却大大减少,从而总体损失得到减少。从出口截面的总压分布也可看出通道涡尺度变大,造成端区总压损失较大。
This paper focuses on the application of bending-twisting blade design method to turbine blade design of turbine with small aspect ratio and aims at analyzing the bending optimization of turbine blade with strong secondary flow through multi-scheme bending design Aerodynamic performance improvement and flow field structure change. The bending design of 14 blades with different height and angle is given. The total pressure ratio and flow rate in these schemes were calculated and analyzed by numerical simulation. It was initially concluded that the reverse bending design in this blade design is superior to the straight and straight blade design, and the reverse bending of 15 ° is the optimal solution. According to the distribution of leaf height along the dense flow, the change of flow capacity in the lower and middle regions of the positive, straight and inverse bending blades was analyzed. Combined with the extreme wall flow pattern and hydrostatic pressure distribution, it can be found that the reverse C-type pressure distribution caused by reverse bending makes the end-zone flow not worsen but worsens, but the low-energy fluid in the middle area is greatly reduced and the total loss is obtained cut back. From the total pressure distribution at the exit cross section, it can be seen that the vortex scale of the passage becomes larger, resulting in a larger total pressure loss in the end zone.