A SIMULATION-MODEL OF A FLOATING HALF ZONE

A simulation model of a floating half zone was suggested by steady num erical simulation and experiment respectively, in the previous papers [Q.S. Chen, W.R. Hu, Int. J. Mass Heat Transfer 40 (1997) 757; J.H. Ha n, Y. Ar, R. Zhou, W.R. Hue, Int. J. Mass Heat Transfer 40 (1997) 2671 ]. In the present paper, the simulation model is studied by using the method of unsteady and three-dimensional numerical simulation, and the transient process from steady convection to oscillatory convection is especially analyzed. Comparison of onsets of oscillation for both sim ulation model and the usual model were obtained, and the results show that the critical Marangoni number of the simulation model is obviousl y smaller than that of the usual model for the same slender liquid bri dge. This implies that the usual model of a floating half zone gives a lower estimation on the onset of oscillation for floating zone convec tion. (C) 1998 Elsevier Science B.V. All rights reserved.