Computational Simulation of Marangoni Convection Under Microgravity Condition

Authors

1 Department of Mechanical Engineering,Sharif University of Technology

2 Department of Mechanical Engineering,Clarkson University

Abstract

In this work, the rising of a single bubble in a quiescent liquid under microgravity condition
was simulated. In addition to general studies of microgravity e ects, the initiation of hydrodynamic
convection, solely due to the variations of interface curvature (surface tension force) and thus the
generation of shearing forces at the interfaces, was also studied. Then, the variation of surface tension
due to the temperature gradient (Marangoni convection), which can initiate the onset of convection even
in the absence of buoyancy, was studied. The related unsteady incompressible full Navier-Stokes equations
were solved using a nite di erence method with a structured staggered grid. The interface was tracked
explicitly by connected marker points via a hybrid front capturing and tracking method. A one eld
approximation was used where one set of governing equations is only solved in the entire domain and
di erent phases are treated as one
uid with variable physical properties, while the interfacial e ects are
accounted for by adding appropriate source terms to the governing equations. Also, a Multi-grid technique,
in the context of the projection method, improved convergences and computational sti ness. The results
show that the bubble moves in a straight path under microgravity condition, compared to the zigzag motion
of bubbles in the presence of gravity. Also, in the absence of gravity, the variation of surface tension force
due to interface curvature or temperature gradient can still cause the upward motion of the bubble. This
phenomenon was explicitly shown in the results of this paper.

Keywords

Scientia Iranica
Volume 16, Issue 6 - Serial Number 6
Transactions on Mechanical Engineering (B)
December 2009

Files

Share

How to cite

Statistics