Numerical study of bubble formation from submerged orifice under reduced gravity condition

The complexity of a multi phase flow in microgravity arises mainly from the fact that the phases can distribute themselves in numerous ways with reduced buoyancy giving rise to a variety of interfacial configurations of different scales. Using Lagrangian smoothed particle hydrodynamics method, efforts have been made to capture interfacial configurations under reduced gravity condition. Further, a diffuse interface approach has been taken to model the evolution of the interface. Simplest interfacial configuration i.e. bubble formation from submerged orifice is modeled to show the extent of complexity can arise in reduced gravity situations. From the numerical snapshots, a periodic detachment and attachment of bubbles with its successor for lower gravity level is observed. Simulations for different air flow rates through orifices and gravity levels show that the rate of periodic attachment and detachment increases with reduction in gravity level and increase in the flow rate. (C) 2015 The Authors. Published by Elsevier B.V.