Calculation And Numerical Simulation Research Of Heat Transfer Of The Aviation Environmental Testing Box

In this paper, a lot of domestic and foreign literature of numerical heat transfer ,heat and transfer and the aricraft cabin temperature requirements is fully unscrambled ,the numerical simulation and numerical simulation software fluent is been in-depth studied and been applied to a air environmental test chamber .The air environmental chamber is used to simulate the temperature distribution in the aircraft cabin and also give the experimental basis to temperature control system .The cabin temperature uniformity,comfort and other requirments of aircraft are described in detail.The air environmental test chamber's insulation structure's influence on air temperature inside is studied.Two programmes using C++ are carried out to compute and also numerical simulation using fluent . In programming calculation of the shape factor is taken into account by introducing cross-border and cross-angle's influence on heat transfer.By writing two programs to calculate the heat transfer process in the box.Also the radiation heat transfer between the box's external high temperature (bare aluminium outer layer of the outer wall and the insulation layer) and external cold air was taking into account to make results more accurate.By comparing the results between full coverage and percentage coverage we can draw a conclusion that external radiation of aluminium layer ocuppies a large proportion throughout the whole heat transfer process. Finally, the laying of the insulation layer under the different requirements was proposed.By using numerical simulation software fluent we simulate the temperature fields in box under two special conditions and draw out the box of typical regional characteristics of temperature fields in sections and providing an intuitive basis for the air environmental test chamber's cabinets environment control's optimal design.By giving different insulation thickness ,we can observe the temperature fields from internal to the outside at low temperature.The fixed heating source is assumed to be a surface heat with uniform heat flux in modeling.So that,we simplify it as a rectangular box uniform heat source which is proportional to the box,heat flux on each side are equal.As the box is regularly shaped and symmetry,but the flow fields are not asymmetric.The paper focuses on the temperature fields when the the heat source is located in the center of box and in the center of the ground of the box.Numerical simulations are respectively.Analysis of visual datas by fluent numerical simulation compare with the results computed by program. Finally we give some recommendations for the air environmental test chamber's insulation structure(insulation layer thickness and coverage,etc.).