Windage Torque and Flow Characteristics of a Co-Rotating Conical Cavity Under Radial Inflow

Abstract

The compressor disk cavity is a critical component of the secondary air system, and its design significantly influences the overall performance of an aero-engine. A static testing technique for dynamic torque measurement was applied for the first time to assess the internal windage torque within a rotating disk cavity. Additionally, the flow characteristics within a rotating cavity of an engine with radial inflow were examined using three-dimensional unsteady Reynolds-averaged Navier–Stokes simulations to elucidate the wind torque law. The primary objective of this study was to quantify the magnitude of windage torque and its variation across various dimensionless parameters. The maximum mass flowrate coefficient and rotational Reynolds number reached 1.50 × 104 and 2.56 × 106, respectively. The results indicated that, under the condition of an inlet pre-swirl of 1, the windage torque in the conical cavity ranged from 0.1 to 1.1 N · m, and the windage torque coefficient ranged from 3.28 × 10−3 to 9.71 × 10−3. The torque coefficient decreased with increasing rotational Reynolds number and increased with rising mass flowrate coefficient. The variations in velocity and pressure loss within the cavity, as a function of dimensionless parameters, followed a pattern similar to that of traditional source-sink flow. This study offers a theoretical foundation and empirical data to enhance the understanding of the temperature rise due to windage, which is essential for the design of disk cavities in high-pressure compressor cavities.