Numerical study on the effect of secondary nucleation on spray cooling

Based on the fundamental principle of spray cooling and bubble-droplet dynamics, a numerical method was developed to study the heat transfer characteristics of heated surfaces with bubbles on them, and the effect of secondary nucleation, secondary nucleation coefficient (α) and secondary nuclei range coefficient (β) on spray cooling was specially studied. The results indicate that increasing the secondary nucleation (α) could result in a rise of the heat flux, but the heat flux does not increase obviously any more when α is greater than 6. The extreme point is reached when β equals 8, and increasing or reducing the β could weaken heat transfer. Compared with the results of Cho, Ponzel, for the cases of α=6， β=3，5，8，10, it was found that β=8 can achieve the best result. Therefore, the prime α, β are 6 and 8.