On the basis of a time-marching code in house

the internal three-dimensional turbulent flow field of a transonic axial compressor Rotor37 with seven tip clearances is numerically studied.The effects of tip clearance flow on aerodynamic performance of the transonic axial compressor rotor are investigated.The results show that

with a decrease in the tip clearance

the aerodynamic efficiency and pressure ratio increase and the stable operation area enlarges significantly.The relationship between the aerodynamic performance and the tip clearance deviates far away from the linear function and appears the curve characteristics.For this rotor

the optimal tip clearance 0.178 mm is a compromise between aerodynamic and structural requirements.