关键词: 涡轮叶片;热斑+;非定常流;薄膜冷却;数值仿真

Abstract: To prevent the turbine blades from overheat induced by combustor hot streaks,two-dimensional unsteady Navier-Stokes simulations were performed on a typical high-pressure turbine stage to study the effects of hot streaks on the airfoils surface pressure and temperature.Such measure as film cooling was tried to protect the turbine blades from overheat caused by hot streaks.Numerical results are consistent well with the available experimental data in open literature.The results show that the existence of hot streaks have little effect on the blades surface pressure,but will lead to time-averaged surface temperature increase on rotor blades especially on pressure surface and augmentation of temperature unsteadiness.Injecting coolants at the gill region on rotor pressure surface have small influence on the blade surface pressure and the migration of hot streaks in turbine stage,but can prevent the hot spots from direct impact on pressure surface to decrease the time-averaged and the fluctuation of surface temperature.

Key words: Turbine blade;Hot streak~+;Unsteady;Film cooling;Numerical simulation