Based on the analysis and summary the some leakage calculation methods characteristics and flow process on the straight through labyrinth seals

the relatively amount of kinetic energy being carried from throttling into the next was considered by use of the theory of two-dimensional (2-D) wall jet and compared with the Vermes method and numerical simulation.The result is that the jet flow in labyrinth cavities has the similar basic characteristics of two-dimensional wall jet flow such as the self-similar distribution of mainstream velocity;an empirical formula developed based on the 2-D wall jet theory is better than that based on the free jet theory and little higher than numerical simulation.