摘要
为揭示转子叶片径向受限的"冲击-气膜出流"冷却结构流动换热规律,以某型双层壁叶片肋化分割形成的冷却单元为研究对象,通过数值模拟的方式,对冲击雷诺数Rej,旋转数Ro,无因次温比(Tw-Tf)/Tw等参数变化下流场和换热特性变化规律展开研究。结果表明:在哥氏力和离心力作用下,受限空间内存在射流偏转、径向二次流动以及二次冲击等现象;流动的径向受限可抑制射流偏转,强化冲击换热;相同的旋转数Ro下,逆转向冲击(叶背区)换热努赛尔数Nu比顺转向冲击(叶盆区)高8%。在研究的参数范围内,数值模拟和试验结果说明径向受限周向出流结构能有效的抑制旋转对换热的削弱。
In order to obtain the rule of flow and heat transfer of ＂impingement-film cooling＂ configuration in limited space of rotating blade,numerical investigation was carried out to study the effects of jet Reynolds numbers Rej,rotation numbers Ro and wall-to-jet temperature difference ratios（Tw-Tf）/Tw.The results show that in the cooling cell,there is deflexion of impinging flow,secondary flow due to Coriolis and centrifugal forces and so on.Besides,the limited space and sparse film cooling stream can increase high heat transfer coefficient on the stagnation point of impingement.Moreover,rotation negative effects to impingement is stronger with same direction impingement（in basin region） than with reverse direction impingement（in back region）.Finally,the results about Nu with varying condition of rotation prove that the structure with limited space and sparse film holes can leash the reduction of efficiency of heat transfer due to the rotation.
出处
《推进技术》
EI
CAS
CSCD
北大核心
2011年第1期125-129,139,共6页
Journal of Propulsion Technology
关键词
冲击冷却
旋转
涡轮叶片冷却
航空推进
换热特性
流动特性
Impinging cooling
Rotation
Cooling of turbine blade
Aerospace propulsion system
Heat transfer characteristic
Fluid characteristic
