Single phase cooling of large surfaces with square arrays of impinging water sprays

Investigation of spray cooling: Effect of different heater surfaces under acceleration

“…Chen et al [5,6] reported that droplet velocity 53 had the most dominant effect on critical heat flux (CHF), followed by 54 the droplet flux, while Sauter mean diameter showed little effect. In 55 the investigation of single phase cooling of large surfaces using square 56 arrays of water sprays, Pereira et al [7] found that coolant mass flux 57 had a strong effect on the single phase heat transfer, while droplet 58 Sauter mean diameter and nozzles discharge velocity had secondary 59 effects. Lin [8] used eight miniature nozzles to conduct the spray cooling 60 and reported that CHF increased as the volumetric flux or pressure drop 61 was increased.…”

Nucleate Boiling in Large Arrays of Impinging Water Sprays

“…This metallic part was mounted inside a polypropylene box thermally insulated with glass wool. Numerical simulations [9] of heat diffusion in the setup, obtained during the test chamber design phase, revealed that, fundamentally, all of the heat would be dissipated through the surface exposed to spray impingement. An outer Plexiglas box, to which a nozzle support plate was mounted, allowed for visual observation of the impingement pattern and spent water collection.…”

“…Information on multiple, overlapping or not, spray nozzle arrangements still is scarce [5][6][7][8][9][10][11]. As in the case of jet arrays, multiple spray nozzles must be positioned in some repetitive pattern if impingement flow heat transfer enhancement is to be extended to the processing of large surface products.…”

“…All coolant transport properties, in this correlation, are to be evaluated at film temperature (average temperature between wall and sprayed liquid). Spray-related parameters, such as calculated droplet Sauter mean diameter, nozzles discharge velocity, and coolant surface tension, were observed to have no measurable effect on the single-phase heat transfer [9,10].…”

“…Such an aspect ratio was successfully employed for correlating the single-phase heat transfer data of in-line spray arrays [9,10]. Equation (2), reproduces all the 230 original experimental points with a mean absolute error of 6.29%: Nu = 5.51e −1/31.4 Re 0.773 Pr 0.609 (2) All the coefficients of Eq.…”