轮缘封严气流与主流涡系交互作用的非定常数值研究

In order to investigate unsteady vortex interaction mechanisms between turbine rotor-stator cavity rim seal flow and mainstream, numerical investigations were conducted for effects of rim seal flow on the secondary flow of mainstream under the condition with and without rim seal flow. The results show that intensity of secondary flow of the stator is weakened due to the blockage effect caused by rim seal flow. In addition, the rim seal flow extrudes secondary flow of the stator and leads to decreasing radial location and area of secondary flow. Besides, the strength of egress flow and radial expansion of rotor hub passage vortex are restrained by hub secondary flow of the stator. The total pressure loss of hub secondary flow of rotor is strengthened by that of the stator. Cavity induced vortex and shear induced vortex are formed due to the induction of rim seal flow. The shear induced vortex is developed into the main part of rotor hub passage vortex. Furthermore, the radial location and intensity of hub secondary flow of the rotor is increased by the shear induced vortex. Due to relative rotation of the stator and rotor, vortex interaction between rim seal flow and mainstream is obviously unsteady.