A mathematic model considering the effect of Brownian motion for subcooled nucleate pool boiling of dilute nanofluids

A new mathematic model was presented to investigate the nucleate pool boiling of nanofluids. The model considered the heat exchange due to Brownian motion of nanoparticles. A new closure correlation is also included in the model to count the active site density and the bubble departure diameter, which were calculated based on the experimental data of a nucleate pool boiling. The new model combines with two-fluid boiling model was used to simulate the nucleate pool boiling process. The simulation focused on the heat transfer due to Brownian motion of nanoparticle. The purpose is to improve surface heat exchange which was induced by the random motion of nanoparticles during the boiling process. The results give a reasonable agreement with the experimental data of nanofluids nucleation boiling with lower heat flux (lower than 100 kW/m2 ) and Nusselt number of 200. The simulation result indicates that the predicted accuracy for a nucleate boiling process of nanofluids can be improved by taking into account both the Brownian motion of nanoparticles and the nucleate site density due to the surface morphology modificatio