Comprehensive investigations on fluid flow and heat transfer characteristics of a high-speed rotating turbine disk cavity system of aero-engine

Abstract

Thermal loading management of turbine disks get important attention in the safety of aero-engines due to a large temperature level and gradient differences in the turbine disk cavity. This study conducts a comprehensive evaluation to address complex heat transfer problems in a high-speed rotating turbine disk cavity system, fully considering multiple factors. A theoretical derivation is conducted to fully elaborate the multifactor influencing mechanisms of the system based on similarity criteria and a dimensional analysis method. Notably, a high-speed rotational experimental platform of rotating disk is established to verify the research method's reasonability and the result's accuracy. Furthermore, four dimensionless operation cases are conducted to assess the correlation mechanism of the system performance with a strong rotating flow and heat transfer. The results indicate that the main correlation factors of the disk cavity system performance are the flowing Reynolds number, rotating Mach number, rotating Reynolds number, specific heat ratio, and wall temperature. Moreover, the Rossby number and the swirl ratio are used to evaluate the fluid flow characteristics. With the increase in the flowing Mach number from 0.006 to 0.15 and the rotating Reynolds number from 0.74 × 106 to 14.80 × 106 at 9000 rpm, the Nusselt number on the rotor disk wall enhances to 1639.4 and 1286.9, respectively. However, it decreases to 1001.91 for the rotating Mach numbers in the range of 1800–13,500 rpm. Particularly, the dimensionless heat flux is in the range of 0.0026–1.23 under multifactor effects. In summarizing, the present findings are of importance for improving the thermal management and performance reliability of aero-engines by developing an advanced turbine disk cooling system.