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为了研究旋转涡轮叶片内部冷却通道的换热特性,将叶片内冷通道简化为带90°直肋的旋转双流程方通道,通过旋转加热实验的方式研究了温度比对旋转直肋双通道换热特性的影响。实验进口雷诺数范围为1×104~5×104,旋转数范围为0~2.02,实验平均温度比分别为0.11,0.16,0.20。研究结果表明,与光滑通道实验数据相比,90°直肋削弱了旋转对换热的影响,同时破坏第二通道后缘面附近的不稳定二次流,造成后缘面换热弱于前缘面;温度比是通过改变冷却空气物性与通道内浮升力对旋转通道换内热特性产生影响,温度比的提高引起的物性变化对通道换热具有削弱作用,静止情况下温度比0.20对应的换热与温度比0.11相比,被削弱程度可达16%,而浮升力对换热具有增强作用;低旋转数下,由温度比引起的浮升力作用与物性作用相互中和,高旋转数下温度比的增大对通道换热特性的增强作用更加明显,并且第二通道换热特性受温度比变化影响较第一通道小。
In order to study the heat transfer characteristics of the cooling channel inside the rotating turbine blade, the internal cooling channel of the blade is simplified as a rotating double-flow side channel with a 90 ° straight rib. The effect of temperature ratio on the rotating straight rib dual-channel heat transfer Effect of characteristics. The experimental inlet Reynolds number in the range of 1 × 104 ~ 5 × 104, the rotation number range of 0 ~ 2.02, the experimental average temperature ratio was 0.11,0.16,0.20. The results show that the 90 ° straight rib weakens the effect of rotation on the heat transfer and destroys the unstable secondary flow near the trailing edge of the second channel, The temperature ratio changes the physical properties of the cooling air and the buoyant force in the channel to change the heat transfer characteristics of the rotating channel. The change of the physical property due to the increase of the temperature ratio has a weakening effect on the heat exchange in the channel, Compared with 0.11, the heat and the temperature are weakened up to 16%, while the buoyancy force has an enhancement effect on the heat transfer. Under the low rotation number, the buoyant force effect and the physical property effect due to the temperature ratio are mutually neutralized, and under the high rotation number The increase of temperature ratio has a more obvious enhancement effect on the heat transfer characteristics of the channel, and the heat transfer characteristics of the second channel are less affected by the change of temperature than the first channel.