Numerical study on spray cooling of aircraft equipment cabin

Abstract

With the increase in the number of aircraft onboard equipment and the sharp increase in heat dissipation power, the thermal control of cabin equipment has become one of the important issues restricting the development of high-speed aircraft technology. Spray cooling has the advantages of high cooling efficiency, simple cooling system structure, easy adjustment and control, etc. It is one of the most effective methods for thermal control of the aircraft equipment cabin. This work builds a simplified physical model of the aircraft equipment cabin, and improves the simulation method of the spray cooling of the equipment cabin. To test the accuracy of the simulation method, an experimental validation study was carried out. In the three-dimensional numerical simulation of cabin spray cooling, the structure characteristics of multi-nozzle spray droplet field, temperature field and flow field are addressed. It’s found that using multi-nozzle spray cooling for large-area and multi-surface equipment cabins is feasible, which can effectively control the temperature of most surfaces. However, for some slit areas, such as between adjacent equipment and between the equipment and the cabin, the temperature is relatively high due to the ineffective coverage of spray cooling. An improved method was applied to investigate the variation of temperature and pressure of the cabin during spray cooling. The study found that the pressure in the cabin can be flexibly controlled by adjusting the size of the exhaust hole of the cabin. The matching of the heating power of the cabin and the spray cooling capacity is an important guarantee condition for realizing the temperature and pressure control of the cabin. This study provides valuable reference data for engineers to design aircraft cabin cooling schemes.