Ultra Fast Spray Cooling and Critical Droplet Daimeter Estimation from Cooling Rate

Muhammad Aamir^1*, Liao Qiang¹, Zhu Xun¹, Wang Hong¹, Muhammad Zubair²

¹Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Chongqing University, Chongqing, China.
²Department of Basic Sciences, University of Engineering and Technology (UET), Taxila, Pakistan.

DOI: 10.4236/jpee.2014.24037                

Abstract

Spray cooling is an effective tool to dissipate high heat fluxes from hot surfaces. This paper thoroughly investigates the effects of spray parameters on the cooling time and cooling rate under varying inlet pressure using water as the coolant. Cylindrical samples of stainless steel with constant diameter, D = 25 mm, and thickness δ: 8.5 mm, 13 mm, 17.5 mm and 22 mm were investigated. Critical droplet diameter to achieve an ultrafast cooling rate of 300°C/s was estimated by using analytical model for samples of varying thickness. At an inlet pressure of 0.8 MPa, maximum cooling rates of 424.2°C/s, 502.81°C/s and 573.1°C/s were achieved for wall super heat ΔT = 600°C, 700°C and 800°C respectively.

Keywords

Spray Cooling; Ultra Fast Cooling Rate; Inlet Pressure; Critical Droplet Diameter

Conflicts of Interest

The authors declare no conflicts of interest.

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