Investigations of the windage in an aero-engine drive cone cavity

This study experimentally and numerically investigates the windage in an aero-engine compressor drive cone cavity. It designs and constructs an adiabatic drive cone cavity experimental system with the capability to measure windage heating. The windage power of the drive cone cavity is obtained by calculating the overall airflow enthalpy rise. The experimental windage moment coefficient C_m results are compared to the predicted results of the drive cone cavity C_m models transformed from the classical rotating disk cavity C_m models. The computational fluid dynamics (CFD) method, validated by experimental data, is utilized to analyze the windage formation mechanism in the drive cone cavity. Based on the C_m modeling theory of classical rotating disk cavities and the CFD results of the drive cone cavity, a simplified drive cone cavity C_m model that better reflects the flow structure is developed. The research results indicate that the variations in windage heating and C_m with nondimensional mass flow rate C_w and rotational Reynolds number Re_ω exhibit opposite trends. The windage heating in the high-radius regions of the drive cone cavity is greater than that in the low-radius regions under the combined effects of viscous dissipation, momentum transfer of viscous shear stress and main vortex entrainment. The viscous dissipation plays a dominant role in windage heating temperature rise. Simplifying the drive cone cavity C_m model based on the flow structure reduces the maximum absolute relative error of C_m prediction results from 29.1% to 15.0% and the average absolute relative error from 13.3% to 8.2%.