04 - Propulsion
LABYRINTH SEALS DYNAMIC COEFFICIENTS AND CRITICAL SPEED RESEARCH BASE OF CHILDS“ MODEL
W. Ma¹, H. Huang¹, G. Feng¹; ¹Shenyang Aeroengine Research Institute, Shenyang, China, China
Mathematical method and computational fluid dynamics (CFD) program are used to calculate the dynamic coefficients and Critical of labyrinth seals. It is important to know the accurate dynamic coefficients of labyrinth seals for predicting the instability of the rotor-seal system. Labyrinth seal dynamic coefficients at ten different radial clearances, eleven pre-swirl ratios, ten rotor speeds, ten seal lengths and three diameters are presented in this paper. The leakage flow rates from the CFD analyses are compared with the results given by a turbulent flow model at fifth different pressures, seal lengths and diameters. Critical speed at fifth seal length and fifth diameters are also studied in this paper. When the gas flows through the tooth cavity, it not only has a large vortex in the labyrinth seal tooth cavity but also a small vortex at the exit of each tooth. Using mesh number and labyrinth seal geometric dimensions change analysis, the results show that the small vortex is significantly influenced by mesh number.