Abstract: Presented are the test results of sealing performance of three types of honeycomb seals, which work under various pressure ratio and rotor speeds. The depth of the honeycomb seal hole is 3.0 mm in all three types of seal. The cell size (the distance between the opposite sides of the hexagonal honeycomb) of the honeycomb seals is respectively 3.2 mm, 1.6 mm and 0.8 mm. The test results show that among the three types of honeycomb seal, the honeycomb seal with a cell size of 1.6 mm enjoys the best sealing performance. This means that the effect exercised by the size of a honeycomb seal cell on the leakage flow does not exhibit a linear relationship. The numerical simulation results indicate that the leakage of honeycomb seals would be at a smaller level due to the stronger turbulent flow and the formation of stronger vortex in the honeycomb cavity，which leads to a better effect of dissipation of the air energy, when the ratio of the cell width to the cell depth is moderate. When the ratio of the cell width to the cell depth is bigger or smaller, the honeycomb seals’ leakage would be at a higher level due to the weaker turbulent flow and the formation of weaker vortex in the honeycomb cavity that leads to a poor effect of dissipation of the air energy.

Key words: Honeycomb seal, Leakage test, Numerical simulation