带射流冲击短扰流柱排内的流动和损失

Pressure fields measurements and flow losses around a row of short cylinder with jet impingement

关键词:  涡轮叶片  扰流器  喷射冲击  实验  流动分布  压力系数

Key words:  Turbine blade  Spoiler  Jet impingement  Experimentation  Flow distribution  Pressure coefficient

摘要:

用五孔探针测量了带射流冲击的短扰流柱排内的流场 ,并用压力扫描阀测量了端壁和柱面的压力分布 ,分析了在涡轮叶片尾缘区内射流冲击强化扰流柱排通道内换热的机理。研究发现 ,带射流冲击时流动在靠近扰流柱表面附近速度较大 ,在对称中心区域有大片低速区 ,压力系数远远小于无射流时情况 ,气流经过孔板后压力系数迅速下降 ,达到最小值 ,沿流动方向压力系数逐渐恢复。随喷射雷诺数增大 ,扰流柱表面的分离点位置后移。总结出了实验工况范围内带射流冲击的短扰流柱排内压力损失系数与雷诺数之间的经验公式 ,便于工程实际应用

Abstract:

The flow fields and pressure fields around a row of short cylinder with jet impingement with pressure scan valve and five hole probe were measured Static pressure distributions on the endwall of channel and cylinder on the surfaces were revealed and studied The experimental data shows that the largest velocity was observed at the place very close to the cylinder surface Velocities decreased rapidly in lateral direction from the surface to the symmetric plane of the channel where low velocity flow was found together with reverse flow and vortex Pressure coefficient was dropped rapidly behind jet plate Then it came back gradually along flow direction The angular position of separation on the surfaces of cylinder was different at different Reynolds number, and it moved downstream while increasing Reynolds number The correlation of pressure loss coefficient, cylinder spacing and distance from jet plate to cylinder with Reynolds number is built based on the experimental data