Experimental and numerical analysis of thermally dissipating equipment in an aircraft confined compartment

Aircraft confined compartments are subject to a wide range of boundary conditions during operation which leads to the setting up of complex internal thermal environments. These compartments require strict thermal management to ensure safe and reliable operation of installed systems. This work investigates the thermal and fluid flow fields in one such compartment the crown area in a fuselage of a commercial aircraft which contains thermally dissipating equipment. Experimental heat transfer and Ply measurements are compared to 3D numerical simulations and are shown to be in very good agreement. There was found to be significant thermal stratification present due to the ventilation not penetrating into the bulk of the fluid. Convective heat transfer coefficients on the surfaces of the dissipating equipment varied as a function of their location, with the highest values occurring when they are placed close to the ventilation inlet. An enthalpic correction was applied to 2D simulations leading to significantly reduced solution times, and results which give a good approximation of the 3D model results.This type of detailed study of aircraft confined compartments is necessary to improve understanding of the flow regimes present in these areas, and leads to optimal positioning of installed systems in terms of thermal management, as well improving global thermal aircraft model predictions.