Effects of initial molten pool and Marangoni flow on solid melting

This study investigated the role of initial molten pool on the numerical si mulation to melting process. The critical time for heat conduction mechanis m to control the formation of initial molten pool is estimated first. A rea listic formulation to the initial molten pool is then proposed. The linear stability characteristics of the initial molten pool when subject to Marang oni flow induced by the perturbations of surface liquid temperature were al so analyzed. For initial pool having a melting time less than the critical time, the subsequent numerical results are independent of the assumed initi al pool. An arbitrarily assumed initial pool could yield erroneous numerica l results for melting. Detailed numerical investigations on the shape evolu tions of molten pool during initial stage and the long-term stage were cond ucted. Effects of the heat transfer intensity and the Marangoni number on t he melting process were also investigated. (C) 2000 Elsevier Science Ltd. A ll rights reserved.