Numerical investigation on bubble dynamics during flow boiling using moving particle semi-implicit method

In the present study, two-dimensional numerical simulation of single bubble dynamics during nucleate flow boiling has been performed using moving particle semi-implicit (MPS) method. A set of moving particles was used to represent the liquid phase. The bubble-liquid interface was set to be a free surface boundary which can be captured according to the motion and location of interfacial particles. The interfacial heat transfer rate was determined by the energy variety of interfacial particles. The bulk liquid velocities investigated ranged from 0.07 to 0.3 m/s. The surface orientations varied from vertical to horizontal through 60 degrees, 45 degrees and 30 degrees. Bulk liquid subcooling varied from 0 to 6.5 degrees C and wall superheat from 2.0 to 20.0 degrees C. The computational results show that the bulk liquid velocity and surface orientation influenced the bubble diameter and liftoff time. Bubble would slide along the heater surface before lifting off and the sliding velocity at liftoff increased with an increase in bulk liquid velocity. Bubble dynamic was related to bulk liquid subcooling as well as wall superheat. The numerical results have been compared with the experimental data. (C) 2010 Elsevier B.V. All rights reserved.