CAJ | 학술논문

为研究燃气轮机叶片表面曲率对气膜冷却性能的影响,对二维斜缝曲面模型（凹面、凸面和平板）进行了数值模拟,选取冷却流体射流入射角35°、主射流密度比1.5,采用RNGk-ε湍流模型计算得到不同吹风比（0.5、1.2和2.0）下斜缝气膜冷却曲面模型壁面的传热系数.结果表明：低吹风比（M=0.5）时,壁面压力梯度越大,传热系数越小;中吹风比（M=1.2）时,射流对主流扰动加剧,传热加强,凹面总体传热系数比凸面小;高吹风比（M=2.0）时,曲率对传热系数的影响减弱,传热系数差异不大.
위연구연기륜궤협편표면곡솔대기막냉각성능적영향,대이유사봉곡면모형（요면、철면화평판）진행료수치모의,선취냉각류체사류입사각35°、주사류밀도비1.5,채용RNGk-ε단류모형계산득도불동취풍비（0.5、1.2화2.0）하사봉기막냉각곡면모형벽면적전열계수.결과표명：저취풍비（M=0.5）시,벽면압력제도월대,전열계수월소;중취풍비（M=1.2）시,사류대주류우동가극,전열가강,요면총체전열계수비철면소;고취풍비（M=2.0）시,곡솔대전열계수적영향감약,전열계수차이불대.
To study the effect of surface curvature on film cooling performance of turbine blade,a numerical simulation was carried out to the two-dimensional slot model for curved（concave,convex and plane） surfaces,during which heat-transfer coefficients on above surfaces were calculated at an injection angle of 35°,a density ratio of 1.5 and at different blowing ratios（0.5,1.2 and 2.0） using RNG k-ε turbulent model.Results show that at a low blowing ratio of 0.5,the heat-transfer coefficient reduces with rising pressure gradient on curved surfaces;at a medium blowing ratio of 1.2,the heat-transfer coefficient is intensified on all surfaces due to enhanced disturbance by injection flow,in which case,the heat transfer on convex surface is weaker than on concave surface;at a high blowing ratio of 2.0,the surface curvature effects little on heat transfer,resulting in basically the same heat-transfer coefficient on all surfaces.