Performance of a Turbine Rim Seal Subject to Rotationally-Driven and Pressure-Driven Ingestion

Abstract This experimental study considered the performance of a chute rim seal downstream turbine nozzle guide vanes (but without rotor blades). The setup reproduced rotationally-driven ingestion and conditions pressure-driven with vanes. maximum speed was 9000 rpm corresponding to rotational Reynolds number 3.3 × 106 flow coefficient 0.45. Measurements mean pressures in annulus disk cavity as well values sealing effectiveness deduced from gas concentration data are presented. At high (low speeds), circumferential pressure variation generated by drove relatively levels into cavity. For given purge rate, increasing led reduction ingestion, shown higher effectiveness, despite presence upstream Uax/(Ωb)=0.45, approached that associated purely ingestion. A map against non-dimensional summarizes results illustrates combined effects on mechanism. imply is relevant parameter important many applications, especially turbines low coefficient.