Session: 01-13: Thermal Management and Aero-engine Oil Systems II

Submission Number: 176117

Development of Numerical Simulation Methods for the Temperature Prediction of an Aero-Engine Gear System 

Gear systems are critical components of aircraft engines, including fan drive gear systems in geared turbofan engines and accessory gearboxes that power auxiliary equipment. In these systems, oil is supplied for both lubrication and cooling to ensure operational reliability. However, in high-speed gear systems, the primary function of oil is cooling. Therefore, optimizing cooling performance can reduce the required oil quantity and further enhance gear system efficiency.

Although numerical simulations using conjugate heat transfer (CHT) are effective for evaluating gear cooling strategies, practical applications of CHT simulations that account for multiple gear meshing and high-speed gas-liquid two-phase flow within gear systems remain limited.

In this study, a novel approach was applied to a planetary gear system by integrating a high-speed gas-liquid two-phase flow simulation method developed by our research team with an accelerated unsteady solid heat conduction calculation method based on Bi–Fo numbers. CHT simulations were conducted to predict gear temperatures during operation. Additionally, infrared thermography was employed to measure gear temperatures under operating conditions and validate the simulation results. Both the CHT simulation and the experiment were conducted using a planetary gear system with dimensions representative of an actual aircraft engine gearbox, operating at a rotational speed corresponding to real engine conditions.

The comparison between simulation and experimental data showed good agreement, confirming the accuracy of the proposed numerical method. The CHT simulation required approximately three times the computational time of flow-only simulations, demonstrating its practicality. Furthermore, simulations were performed under varying lubrication quantities to investigate their impact on gear temperature.

Presenting Author: Hironori Hashimoto Kawasaki Heavy Industries, Ltd.

Presenting Author Biography: Hironori Hashimoto is a researcher who belongs to Energy System Research Department at Technical Institute of Kawasaki Heavy Industries, Ltd. He received a master's degree from Kobe University. He is mainly engaged in CFD simulation on heat and oil management in gear systems of aircraft engines.

Authors:

Hironori Hashimoto Kawasaki Heavy Industries, Ltd.
Hidenori Arisawa Kawasaki Heavy Industries, Ltd.
Yuji Shinoda Kawasaki Heavy Industries, Ltd.
Tomoyuki Hamasaki Kawasaki Heavy Industries, Ltd.
Isao Fujii Kawasaki Heavy Industries, Ltd.
Akihito Abe Kawasaki Heavy Industries, Ltd.