平流层飞艇载荷舱电子设备散热仿真分析

Stratospheric Airship Payload Compartment Electronic Equipment Thermal Simulation Analysis Research

飞艇载荷舱电子设备的温度极大地影响了其工作可靠性,随着飞艇载荷舱应用途径的拓展,载荷总功率不断增长,设备设计功耗及热流密度显著提升,但平流层气体密度仅为地面的1/18,对流散热能力差,散热问题逐渐成为制约技术发展的关键问题。文章为了解决高载荷功率下的散热痛点,引入了两相流体回路散热方法,探究其与风扇强迫散热的散热能力,在分析载荷舱电子设备传热特性的基础上,基于计算流体力学,设计了风扇强迫对流散热系统,同时提出一种采用1,1,1,2-四氟乙烷(R134a)流体回路对平流层载荷舱电子设备散热的方法,并使用表观热容法对其进行仿真,计算了两种散热方式下飞艇载荷舱的温度场和流场,得到了两种方式的散热能力。仿真结果表明,风扇的散热极限工率约为591 W,两相流体回路方式散热可以解决700 W的散热需求,使用风扇散热可以满足基本散热需求;使用两相流体回路方式散热可以对平流层飞艇载荷舱电子设备进行有效热控,为平流层大功率电子设备散热的设计和计算提供思路。

The temperature of electronic equipment in the payload compartment of an airship greatly affects its operational reliability.As the application scope of the airship payload compartment expands,the total power of the payload continues to increase,leading to significant increases in equipment design power consumption and heat flux density.However,the density of the atmosphere in the stratosphere is only 1/18 of that at the ground level,resulting in poor convective heat dissipation capability.Heat dissipation has gradually become a key issue restricting technological development.To address the thermal pain points under high payload power,this article introduces the two-phase fluid loop heat dissipation method and explores its heat dissipation capability compared to fan-forced heat dissipation.Based on the analysis of the heat transfer characteristics of electronic equipment in the payload compartment,a fan-forced convection heat dissipation system is designed based on computational fluid dynamics.Simultaneously,a method for using a 1,1,1,2-tetrafluoroethane(R134a)fluid loop to dissipate heat in the stratospheric payload compartment for electronic equipment is proposed,and its simulation is conducted using the apparent heat capacity method.The temperature and flow fields of the airship payload compartment under the two heat dissipation methods are calculated,obtaining the heat dissipation capabilities of the two methods.Simulation results indicate that the heat dissipation limit of the fan is approximately 591 W,while the two-phase fluid loop heat dissipation method can meet the heat dissipation requirement of 700 W,thus fulfilling the basic heat dissipation needs.The use of the two-phase fluid loop heat dissipation method can effectively control the temperature of electronic equipment in stratospheric airship payload compartments,providing insights into the design and calculation of heat dissipation for high-power electronic equipment in the stratosphere.