Numerical Simulation And Experimental Study Of Spray Cooling Heat Transfer Characteristics

At present,with the rapid development of electronic technology and laser technology industry,these electronic devices and lasers can generate high heat flows in the work,which can reach hundreds of watts and even several kilowatts per square centimeter.And their optimal working temperature generally does not exceed 75°C.Spray cooling has a wide application prospect in the heat dissipation of high-power devices due to its small heat transfer heat resistance,good heat transfer performance,low temperature gradient,non-boiling hysteresis,and low demand for working fluid.At present,most researches mainly focus on the enhancement of heat transfer,while most researches on surface wetting characteristics focus on pool boiling.In this paper,through numerical simulation and experimental research,the heat transfer characteristics of spray-cooled non-boiling zone are studied,and the effect of surface characteristics on heat transfer characteristics is mainly studied.The specific research content is as follows:1.Based on the Euler-Lagrangian model,a numerical model of spray cooling heat transfer was established,and parameters such as heat input heat flow,nozzle height,and cooling medium flow rate were changed to explore its influence on spray cooling heat transfer characteristics.The analysis focused on the distribution characteristics of hot surface temperature,liquid film thickness and flow velocity.2.Built a spray cooling experiment platform.The basic parameters of the experiment included the influence of nozzle height,nozzle flow rate and heating power on the heat transfer characteristics of spray cooling.It was found that the influence of these parameters on spray cooling performance was consistent with the numerical simulation results.3.Change the surface roughness and surface wetting characteristics,and explore the spray cooling heat transfer performance of different roughness surfaces and superhydrophilic/superhydrophobic surfaces in the non-boiling regime.It was found that the change in roughness did not significantly enhance spray cooling heat transfer.Compared to smooth surfaces,superhydrophilic /superhydrophobic surfaces would worsen heat transfer.