蜂窝密封的封严特性研究

EXPERIMENTAL AND THEORETICAL INVESTIGATION OF THE SEALING PERFORMANCE FOR HONEYCOMB SEALS

对于蜂窝深度为3.0mm、蜂窝芯格尺寸(蜂窝六边形的对边距离)分别为3.2mm、1.6mm和0.8mm三种蜂窝密封,研究了在不同转速、压比下的封严特性。试验结果表明,三种蜂窝密封之中,芯格尺寸为1.6mm的蜂窝密封封严效果最好,说明蜂窝密封芯格尺寸的大小对其漏气量的影响并不呈线性规律。计算结果表明,蜂窝宽度与蜂窝深度比值适当时,能量耗散效果好,密封的漏气量较小。蜂窝宽度与蜂窝深度的比值偏大或偏小时,能量耗散效果差,密封的漏气量都较大。

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 honey- comb) of the honeycomb seals is respectively 3.2 mm, 1.6 mm and 0.8 mrn. 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 nu- merical simulation results indicate that the leakage of honey- comb seals would be at a smaller 1evel due to the stronger tur- bulent flow and the formation of stronger vortex in the honey- comb 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.