Sealing efficiency performance of four different rim seals in turbine cavity

Abstract

In modern aero-engine, the turbine rim seals whose purpose is to reduce the ingress are located in a complex flow region between the mainstream and secondary air flows. The sealing air discharged from the compressor of engine is used to purge turbine cavity. In order to examine the effects of ingress through four distinct rim seals, a one-stage test rig was used in the experiments presented in this work. At a Reynolds number of 5.16 × 105 in the mainstream and (0.85–2.13) × 106 in the rotational, the radial pressure distribution on the stator was determined. To assess flow characteristics and sealing efficacy, measurements of the swirl ratio and CO2 concentration were made. The reliability of turbine rim-seals is determined by the locations of the hook and teeth, as well as their effect on hot gas ingestion. To evaluate the performance of four types of seals: a datum double-rim seal and three derivatives with different clearances, the data are employed. Due to the inlet air position, the swirl ratio exhibited a pronounced inflection for all the rim seals. The sealing efficiency can be decreased by putting the hook closer to the rim or by taking the teeth out. Static pressure measurements in the turbine cavity indicate that the seal position has a significant impact. The analysis results revealed that the existence of slot vortex is beneficial to improving efficiency.