摘要
采用基于雷诺平均N-S方程的三维CFD计算程序,并结合Spalart-Allmaras一方程或k-epsilon双方程湍流模型加壁面函数的方法,对涡轮平面叶栅和涡轮级转子的叶尖间隙流场进行了数值计算,详细研究了不同叶尖间隙高度、不同叶尖间隙形式和叶尖间隙有冷气入射时其对涡轮叶尖间隙流场和性能的影响。计算结果表明:叶尖间隙对从大约70%叶高到叶尖位置的叶片损失具有明显的影响;在同样间隙大小情况下,余高间隙叶片等熵效率比平间隙叶片等熵效率约提高了一个百分点;而叶尖间隙有冷气入射时涡轮的等熵效率要比无冷气入射时的等熵效率约提高两个百分点。
By using the three-dimensional CFD(Computational Fluid Dynamics) calculation program based on Reynolds-averaged N-S equation and coupled with the method of a turbulent flow model based on Spalart-Allamras single equation or k-ε dual equations plus wall surface functions,a numerical calculation study has been performed of the blade tip leakage flow field of a turbine plane cascade and rotor.The influence of different blade tip clearance heights and forms as well as the blade tip clearance with an incidence of cold air on the turbine blade tip clearance flow field and performance was studied in detail.The calculation results show that the blade tip clearance has a conspicuous influence on the blade loss at locations from about 70% blade height to blade tip.Under the condition of an identical blade tip clearance,the isentropic efficiency of an excess height clearance blade is approximately one percentage point higher than that of an equal height clearance blade while the isentropic efficiency of a turbine having a blade tip clearance with an incidence of cold air is about two percentage points higher than that of a turbine without an incidence of cold air.
出处
《热能动力工程》
CAS
CSCD
北大核心
2009年第4期432-436,共5页
Journal of Engineering for Thermal Energy and Power
关键词
涡轮
涡轮性能
间隙流动
泄漏涡
流场计算
turbine,turbine performance,clearance flow,leakage vortex,flow field calculation
