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Numerical Modeling of Liquid-Vapor Phase ChangeWe implemented a two- and three-dimensional finite difference/front tracking technique to solve liquid-vapor phase change problems. The mathematical and the numerical features of the method were explained in great detail in our previous reports, Briefly, we used a single formula representation which incorporated jump conditions into the governing equations. The interfacial terms were distributed as singular terms using delta functions so that the governing equations would be the same as conventional conservation equations away from the interface and in the vicinity of the interface they would provide correct jump conditions. We used a fixed staggered grid to discretize these equations and an unstructured grid to explicitly track the front. While in two dimensions the front was simply a connection of small line segments, in three dimensions it was represented by a connection of small triangular elements. The equations were written in conservative forms and during the course of computations we used regriding to control the size of the elements of the unstructured grid. Moreover, we implemented a coalescence in two dimensions which allowed the merging of different fronts or two segments of the same front when they were sufficiently close. We used our code to study thermocapillary migration of bubbles, burst of bubbles at a free surface, buoyancy-driven interactions of bubbles, evaporation of drops, rapid evaporation of an interface, planar solidification of an undercooled melt, dendritic solidification, and a host of other problems cited in the reference.
Document ID
20010021332
Acquisition Source
Glenn Research Center
Document Type
Contractor or Grantee Report
Authors
Esmaeeli, Asghar
(Michigan Univ. Ann Arbor, MI United States)
Arpaci, Vedat S.
(Michigan Univ. Ann Arbor, MI United States)
Date Acquired
September 7, 2013
Publication Date
February 15, 2001
Subject Category
Physics (General)
Report/Patent Number
DRDA-98-3449
C034943
Report Number: DRDA-98-3449
Report Number: C034943
Funding Number(s)
CONTRACT_GRANT: NAG3-1952
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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