Research on the influence of structural parameters and optimization of heat sinks for high-power helicopter intermediate gearboxes

Abstract

The intermediate gearbox of high-power helicopters needs to withstand higher loads and greater heat dissipation requirements. Relying solely on the casing shell for heat dissipation can no longer meet its cooling demands, necessitating the addition of heat sinks on the casing surface to enhance heat transfer capability. This study simplifies the high-temperature surface of the intermediate gearbox casing into a flat plate of uniform thickness and investigates the influence of heat sink structure on the plate's cooling capacity through experimental and numerical simulation methods. Using CFD simulation and infrared thermography, the simulation results were compared with experimental data, revealing an average error of 1.01 %, which verifies the accuracy of the CFD simulation and confirms the V-shaped heat sink as the optimal configuration. Analysis of the effects of heat sink height, width, spacing, and width-to-spacing ratio shows that increasing height improves heat transfer performance by 12.9 %, increasing width reduces it by 12.2 %, increasing spacing improves it by 13.6 %, and increasing the width-to-spacing ratio decreases it by 27.3 %. When the optimized heat sink parameters were applied to the bottom casing of a certain high-power helicopter intermediate gearbox, temperature field simulations demonstrated that the optimized heat sinks reduced the maximum temperature at the casing bottom by 14.7K and the oil temperature by 5.8K.