旋转状态下篦齿流量特性试验研究

篦齿是航空发动机中非常重要的密封流动单元。本文用试验方法研究了2齿和10齿直通型篦齿在旋转状态下的流量特性,获得了篦齿流量特性随进出口压比的变化关系,同时测量了不同转速下篦齿各齿间压力。结果表明:在低压比(<1.8)、低转速(<1 000 r/min)情况下,旋转对篦齿流量特性影响较小;但随着转速的升高,同一压比下,流量系数会降低,在转速2 500 r/min时,流量系数比静止状态时降低了约8%,齿间压力也有一定程度的下降。

Experimental Investigation on Leakage Flow Characteristics in Rotating Labyrinth Seals

Labyrinth seals represent an important flow element in sealing equipments of modern aeroengine.This paper investigates experimentally the leakage flow characteristics of both two teeth and ten teeth straight-through rotating labyrinth seals.The influence of pressure ratio on the leakage flow characteristics of the both labyrinth seals is obtained.The pressure ratio is defined as the outlet static pressure divided by the inlet total pressure.Furthermore,the pressures between teeth are measured in different rotate speeds.The results show that the changes in leakage flow characteristics are little at low pressure ratio(<1.8) and rotational speed(<1000r/min).With the rotate speeds increase at the same pressure ratio,the flow coefficient decreases.Especially,when the rotational speed is up to 2500r/min,the flow coefficient decreases about 8% than that of static state,also the pressures between teeth decrease.