Simulation of the non-uniform temperature-field evolution of a high-pressure rotor after engine shutdown

Abstract The high-pressure rotors in aircraft engines endure substantial thermal loads during operation. After shutdown, a temperature gradient develops within the casing, with cooler conditions at the bottom and hotter conditions at the top. This results in non-uniform heating of the rotor, leading to thermal bending. In this study, steady-state and transient thermo-mechanical coupling models are established for a high-pressure rotor, enabling accurate simulation of the evolution of its non-uniform temperature field during natural cooling. The temperature evolution characteristics at different rotor locations are analyzed. The simulation results demonstrate that, under ambient cooling conditions (30 °C), the rotor requires approximately 17 h to cool from the high-temperature shutdown state to thermal equilibrium at 30 °C. The turbine disk exhibits higher temperatures at its upper edge and lower temperatures at the lower edge, with a maximum temperature difference of 48 °C occurring within 0.86 h during natural cooling. During the cooling process, the center temperatures of both the turbine and compressor disks initially rise before gradually decreasing, with the temperature beginning to decline after approximately 0.15 h of natural cooling.