Abstract: The honeycomb at the inner band of the compressor stator and the labyrinth on the disk form a sealed cavity, and the clearance leakage flow in the cavity has an important influence on the aerodynamic performance of the axial flow compressor. In this paper, the first 1.5 stage of a lowspeed research compressor (LSRC) was taken as the research object, and the influence of honeycomb seal structure on the aerodynamic performance of the compressor compared with the slide wall and honeycomb seal structure at two kinds of labyrinth seal clearance was discussed by numerical simulation. The performance calculation results show that the isentropic efficiency of the 1.5-stage compressor using the honeycomb cavity model of 0.2mm clearance is slightly lower than that of the slide wall cavity model because of the higher total temperature rise caused by the leakage flow in the cavity. A comparison of cavity leakage flow characteristics and a detailed flow field analysis shows that the honeycomb structure simultaneously increases the cavity leakage flow and swirl angle. The airflow within the cavity and the honeycomb interact strongly, creating a complex vortex flow that significantly raises the total temperature in both the seal cavity and the honeycomb. This increase in temperature ultimately reduces compressor efficiency. Compared with the zeroclearance honeycomb model and the 0.2mm clearance honeycomb model, the decrease in total temperature ratio leads to an increase in isentropic efficiency. The leakage flow and swirl angle of the zero-clearance model are greatly reduced, and the mixing loss of leakage flow does not change significantly. In the zero-clearance model, although the average total temperature of the leakage flow increases due to the decrease of the clearance, the compressor efficiency improves due to the substantial reduction of the leakage flow rate. The research results of this paper reveal the quantitative relationship and mechanism of the influence of leakage flow at different clearances on the performance of the honeycomb and the labyrinth seal structure of the stator in the actual compressor, which has a certain reference value for the engineering design of the honeycomb seal cavity.

Key words: low-speed research compressor (LSRC), honeycomb, labyrinth, seal clearance, leakage