Numerical simulation of heat transfer and fluid flow of molten metal in lost foam casting (LFC) process

In this study fluid flow and heat transfer of lost foam casting (LFC) process are being evaluated. Finite difference explicit form of SOLA-VOF algorithm with donor-acceptor method is used to simulate fluid flow with free boundaries. To add the effect of gas pressure produced in the result of heat transfer between molten metal and foam, a 2D foam destruction model is presented for the first time. In this model based on the mass and energy balance between gas and molten metal, radiation and conduction between foam and molten metal; and convection between gas and molten metal are considered. Simulation results are compared with some data reported in the literature which show good agreement. It is found that besides radiation in the gaseous area between foam and molten metal, conduction also plays an important role in foam destruction and control of molten metal velocity. Analyzing effects of different parameters on foam casting process shows that coating thickness, foam density and vacuum pressure have considerable effect on the pressure in the gaseous area between foam and molten metal and also on molten metal velocity and also ideal gas assumption can predict the behavior of gas produced from foam destruction in a good manner.

کلیدواژه ها:

Lost foam casting (LFC) ، Numericalsimulation ، Foam destruction model ، gap pressuremodeling