摘要
在涡轮发动机叶栅通道内引起不稳定流的主要因素之一便是上游叶片尾迹的传播,尾迹将使得涡轮叶片表面上不稳定的层流向湍流边界层过渡,从而导致转捩提前。从边界层转捩理论的角度入手,预测了尾迹对叶片表面换热特性的影响。首先,引入尾迹诱导时间平均间歇因子修正湍流间隙因子;其次,采用相平均湍流度预测尾迹诱导下转捩起始点;最后,引入尾迹产生的湍流黏性系数修正叶片层流区有效黏性系数。结果表明:尾迹影响换热特性的算法研究与改进在相关实验系统上得到较好的验证,显著提高了尾迹影响下的换热计算精度。
One of the main factors causing unstable flow in the turbine cascade channel is the propagation of upstream blade unsteady wake.The unsteady wake advances the transition from unstable laminar flow to turbulent boundary layer on the surface of turbine blades,leading to an earlier transition.The influence of unsteady wakes on the surface heat transfer characteristics of turbine blades was predicted based on boundary layer transition theory.Firstly,the unsteady wake-induced time-averaged intermittency factor was introduced to correct the turbulence intermittency factor.Secondly,the phase-averaged turbulence intensity was used to predict the onset of transition induced by the unsteady wake.Finally,the turbulent viscosity coefficient generated by the unsteady wake was introduced to correct the effective viscosity coefficient in the laminar region of the blade.Results show that the computational method and improvement for the unsteady wake influence on turbine blade surface heat transfer characteristics have been well validated in relevant experimental systems,significantly improving the accuracy of heat transfer calculations under the unsteady wake influence.
作者
张正
朱惠人
张丽
姚春意
徐志鹏
薛树林
李亚雄
ZHANG Zheng;ZHU Huiren;ZHANG Li;YAO Chunyi;XU Zhipeng;XUE Shulin;LI Yaxiong(School of Power and Energy,Northwestern Polytechnical University,Xi'an 710072,Shaanxi Province,China;Hunan Aviation Power Plant Research Institute,Aero Engine Corporation of China,Zhuzhou 412002,Hunan Province,China)
出处
《动力工程学报》
北大核心
2025年第6期828-834,923,共8页
Journal of Chinese Society of Power Engineering
基金
国家科技重大专项资助项目(J2019-III-0019-0063)。
关键词
涡轮叶片
尾迹
换热特征
边界层转捩
间歇因子
黏性系数
turbine blade
unsteady wake
heat transfer characteristics
boundary layer transition
intermittency factor
viscosity coefficient
