bubble dynamics and nucleate pool boiling of natural convection

The phenomenon of nuclear boiling has always been recognized suitable for heat transferbetween different boiling regimes. study on boiling is considered as a new field which meetsdifferent research and industrial needs such as heat transfer in nuclear reactors, cooling units,rocket motors, electronic equipment cooling, batteries, etc. in this study, a chamber withimmiscible fluid, water, steam, and air, having a side wall with uniform heat flux has been studiedin 3d. to do so, we first considered the prediction of the heat flux interval for which the boilingoccurs in the form of nuclear boiling. in this study, two-phase fluid volume (vof) approach wasused for modelling boiling on the vertical wall and two-phase flow. in this research, ansyssoftware package was used for numerical modelling and numerical simulation. distribution ofthe velocity field follows more uniform pattern in dimensionless heights less than 0.9. in thisstudy, bubbles are only present near a wall with heat flux that has a lower rayleigh number.also, existence of these bubbles on the wall, which prevents fluid infiltration, affects vorticescaused by natural convection. however, the general and uniform patterns of vortices remainunchanged in most part of the fluid, which is because of the limited amount of bubbles near thewall with heat flux. natural convection increases the height of fluid inside the chamber, whichleads to the formation of stronger vortices at a dimensionless height of 0.9 that has a high raleighnumber due to high heat flux. in this case, the continuous use of heat flux gives rise to theproduction of bubbles over time.