Numerical study of high-overload effect on liquid film of spray cooling

Experimental Investigation on Heat Transfer Mechanism of Air-Blast-Spray-Cooling System with a Two-Phase Ejector Loop for Aeronautical Application

“…Besides, the heat transfer coefficient under a smaller heating power increases faster than that under a larger heating power. Combining with pattern (b), it is obvious that the temperature under a smaller heat flux is lower than that under a larger heat flux, indicating that the target surface temperature is closer to the water inlet temperature, due to the calculated mode of the heat transfer coefficient Equation (4). The heat transfer coefficient is inversely proportional to the temperature difference between the target surface temperature and the water inlet one.…”

“…In general, either convectional air-cooling or liquid-cooling is the available single-phase method for dissipating waste heat nowadays [3], and the latter option is more attractive due to its high thermal load ability than the former one. However, when a higher level of heat fluxes generated and face more complicated working conditions such as overload in the aeronautical environment, liquid-cooling techniques often cannot gain sufficient heat dissipation capacity and achieve a relatively stable performance [2,4]. Tremendous studies regarding the heat transfer attainability and discovered that the two-phase convection could afford two-to three-orders-of-magnitude higher heat transfer coefficients over single-phase convection in addition to maintaining closer temperature tolerances [2][3][4][5][6].…”

“…However, when a higher level of heat fluxes generated and face more complicated working conditions such as overload in the aeronautical environment, liquid-cooling techniques often cannot gain sufficient heat dissipation capacity and achieve a relatively stable performance [2,4]. Tremendous studies regarding the heat transfer attainability and discovered that the two-phase convection could afford two-to three-orders-of-magnitude higher heat transfer coefficients over single-phase convection in addition to maintaining closer temperature tolerances [2][3][4][5][6]. Spray cooling is considered as one of the most effective methods of high-flux-waste-heat removal and has long enjoyed a reputation of unavoidable cooling method [7].…”

“…For the purpose of enhancing the heat dissipation capacity of SCS, tremendous efforts regarding the complicated heat transfer mechanisms have been carried out through both numerical simulation studies and experimental investigations in different conditions. Many parameters affect the thermal performance such as arrangement of multi-nozzle [5], heat transfer surface roughness [6], coolant type [12][13][14], spray flow rate [13,[15][16][17], spay height [18], spray angle [19], nozzle inlet pressure [20], droplet size [21], impact velocity [22], gravity [4,23], target surface structure [24][25][26][27], and sub-cooling degree [28,29], which all have been contributed to the variation in behavior of spray cooling technology. Furthermore, each of the factors is mutual interference and restriction [7], for instance, the factors of droplet size, impact velocity, spray angle, even the spray flow rate would change as the variation of the nozzle inlet pressure.…”

Numerical Investigation on the Thermodynamic Characteristics of a Liquid Film upon Spray Cooling Using an Air-Blast Atomization Nozzle

“…During the last several decades, the miniaturization, as well as the highly integrated, high-density device packaging, and inefficiency of electronics have evoked great interest in modern industry and a wide variety of aids from industrial and environmental fields have been applied [1,2], for instance, ground-based devices like the lateral diffused metal oxide semiconductor field effect transistor (LD-MOSFET) [3] and space devices like the NASA Goddard mars orbiter laser altimeter [4]. However, large amounts of waste heat generated at high heating power, cause a super high temperature so as to decrease the service lifetime and efficiency of the electronic devices.…”