Numerical Study of Solidification in Cavity with the Presence of Natural Convection

Abstract

A study of Laminar two dimensional transient solidification with time –dependent natural convection in the melt is carried out. The mathematical modelfor the numerical simulation is based on enthalpy porosity method. The governingequations are descritized on a fixed grid by means of a finite volume technique.The (SIMPLE) procedure was adopted to solve mass, momentum and energyequations for pure phase change material (water) placed in a cooled rectangularcavity. The cavity was cooled from top alone, right side wall alone, and right sidewall with top and bottom walls together. In the case of top cooling a parabolicshaped pattern of ice water interface was formed. For the right side wall coolingthe effect of density changes has led to an abnormal flow circulation which hasmoderately modified the heat balance of the freezing interface causing a collidingof cool and warm fluid layers. A density variation was seen in the freezinginterface region in most of the cases. The results obtained show good agreementwith experimental and numerical results of other researchers for pure convectionwith small discrepancies in the ice interface. These discrepancies may beattributed to the physical modeling used for water freezing.