On CFD investigation of radial clearance of labyrinth seals of a turbine engine

Anotace: Fluid flow in labyrinth seals of a turbine engine is described. The aim is to describe numerical calculations of fluid flow in labyrinth seals and evaluate the calculated data for different settings of radial clearance of labyrinth seals. The results are achieved by 3D CFD detailed simulations in a typical seal geometry. The calculations are performed for different radial clearances at a constant pressure drop. The calculated data are evaluated based on mass flow, static pressure, total enthalpy and total temperature of air. Based on the calculated data, it is visible, that the total temperature of air is increased in the labyrinth seals. The static pressure of air acts as expected –the static pressure is decreased in all teeth. The Mach number is similar in all teeth, but the maximal maximum value is in the last tooth, because of the expansion into the ambient conditions. Results of the calculations are that the total temperature in labyrinth seals is not constant as it is usually presented or supposed usually in common literature.