Single Bubble Dynamics During Flow Boiling on a Horizontal Surface at Different Gravity Levels

Complete numerical simulations of bubble dynamics including bubble growth, sliding motion, and bubble lift-off from a horizontal surface have been carried out for different gravity levels and flow velocities. In the model, the region of interest is divided into micro and macro regions. The micro region is the ultra thin liquid film that forms between the solid and evolving vapor-liquid interface. The region occupied by vapor and liquid—excluding the micro layer—is designated as the macro region. Complete conservation equations of mass, momentum, and energy for both phases are solved in this region. The interface shape is obtained by solving for the Level-Set function. The advancing and receding contact angles obtained from experiments are used as input to the model. The predictions are compared with data from experiments. The functional dependence of bubble diameter at departure and growth period on gravity is found to weaken with the increase in flow velocity.