Optimization Design and Research on Labyrinth Seal Structure of Wave Rotor

Abstract

Abstract. As a rotating device, the wave rotor has two key clearances during operation: one between the port and the rotor end face, and the other between the rotor and the casing. These clearances directly cause gas leakage, resulting in significant losses and reducing operational efficiency. As a mature noncontact sealing technology, the labyrinth seal is widely used in wave rotors due to its noncontact sealing characteristic. Its core principle is to increase the flow resistance of the gas leakage path through a special structure, thereby reducing the leakage amount to mitigate losses. To improve the performance of the wave rotor's labyrinth seal, this study takes the traditional 45 deg inclined tooth labyrinth seal as the basis, introduces two new structures (cross baffle and inclined baffle), and explores the sealing performance of these structures through simulation analysis. The results show that the sealing effect of the structure with baffles is significantly improved: on one hand, it enhances the vortex dissipation effect in the tooth cavity to consume the energy of leaked gas; on the other hand, it strengthens the flow contraction effect in the clearance to reduce the leakage amount per unit time, ultimately improving the axial sealing performance. In terms of data, the maximum reduction in leakage of the labyrinth seal with the inclined baffle is 10.86%, and that with the cross baffle is 22.32%.