基于内外环境耦合的客机表面温度的预测

Prediction of Aircraft Surface Temperatures based on the Onboard and Outboard Coupling

准确预测客机表面温度对评价舱内环境的舒适性以及墙体的保温性能具有重要意义。目前大多数研究忽略舱内外环境间耦合的传热过程,近似认为舱内表面温度是均匀的。本文以计算流体力学(CFD)为主要工具,建立了包含金属蒙皮、保温层以及舱内空间为计算域的CFD模型。舱内采用S2S辐射模型与RNG k-ε湍流模型耦合的方法,蒙皮外壁面赋以对流与辐射混合边界参数,并考虑飞机巡航高度、天空、地面和太阳辐射等外部因素以及舱内对流与辐射等内部因素对机身传热的影响。计算结果表明,舱内壁面温度不十均,飞行高度对舱内壁面温度影响较大,而太阳辐射、客舱送风位置等对舱内表面的温度影响相对较小。

Accurate prediction of aircraft surface temperature is critical to evaluate cabin environment and heat insulation performance of the aircraft walls. However, most of the current practices omit the coupled relation between the onboard and outboard air environments and assume uniform wall surface temperature for simplicity when studying the internal cabin environment. A Computational Fluid Dynamics （CFD） model is established in this investigation, with the solution domain covering the metallic shell, insulation, and interior aircraft cabin space. The RNG κ-ε turbulence model was coupled with the S2S radiation model for temperature prediction： The outer shell skin surfaces were assigned with boundary parameters of mixed convection and radiation. Impacts of flight altitude, sky, ground and solar radiation were taken into account accordingly. The results reveal that aircraft skin surface temperatures are not uniform. The interior cabin surface temperature is more sensitive to the flight altitude than the solar radiation and the cabin air-supply locations.