The Impact of Wall Hole Quantity on the Sealing Performance and Vortex Distributions in Wall-Hole-Honeycomb Seal

The structure of honeycomb seal (HCS) has a significant impact on its sealing performance. Our previous research proposed a novel honeycomb seal structure called the wall-hole-honeycomb seal (WHHCS). The WHHCS can further improve the sealing performance of HCS, including double-wall-hole-honeycomb seal (D-WHHCS) and single-wall-hole-honeycomb seal (S-WHHCS). To delve into the influence of wall hole quantity on the WHHCS, the leakage characteristics of the two configurations are investigated using the computational fluid dynamics (CFD) method. The vortex structures and distributions in both seals were examined based on the Q-criterion. The results show that increasing the number of wall holes improves the leakage suppression capability of WHHCS, with a 36.5% enhancement observed when changing from a single to a double wall hole configuration. The number of wall holes also affects the vortex and streamline distributions in cavities, leading to a U-shaped vortex structure in S-WHHCS at lower Q values. At higher Q values, different vortex morphologies are observed in the left and right wall hole regions of D-WHHCS, with the left wall hole exhibiting a more pronounced effect on leakage reduction. Furthermore, D-WHHCS exhibits a 10.3% larger vortex volume in the sealing gaps and a 16.7% larger vortex volume in the cavities than S-WHHCS. The larger volume of high-Q vortex regions gives the D-WHHCS a clear advantage in leakage reduction over the S-WHHCS. This study provides guidance for further structural optimization of WHHCS.