Progress of aerospace-based spray cooling applications

The heat flux generated by electronic components increases dramatically since the integration andminiaturization of electronic components have been extensively proposed (Chen et al., 2021; Teng et al., 2022). Huge generated amounts of heat and the decrease of heat dissipation area lead to the sharp increase in heat flux of the devices (Wang et al., 2015; Wang et al., 2022a). In some specific applications such as air-borne high energydensity directional weapons, the heat flux of electronic devices has been achieved at 10 W/cm (Wang et al., 2021a). Thermal management becomes a key bottleneck in technology development because the service life, reliability, and stability of electronic devices are affected by the overheating caused by untimely dissipation of heat flux (Chen et al., 2022). Traditional single-phase cooling can no longer satisfy the demand of current heat dissipation, while the phase change process can absorb large amounts of heat (Hao et al., 2022), such as microchannel cooling (Zhang et al., 2021), jet impingement (Overholt et al., 2005) and spray cooling (Wang et al., 2017), which are now considered as highlyefficient methods that can take away a large amount of heat. Spray cooling is considered to have the advantages of large specific surface area, small coolant flow rate, small temperature difference between surface area and working medium, and high heat flux removal ability comparing other cooling methods (Wang et al., 2018c). Therefore, spray cooling technology has always been a hot technology in the field of electronic cooling, especially in the aerospace field with high heat dissipation requirements such as diode array, large radar, laser transmitter, and satellite electronics (Wang J. X. et al., 2016) as shown in Figure 1A,B. Thus, the operating principles, the influence factors, and prospects for aerospace-oriented spray cooling research have been reviewed in this paper.