NUMERICAL STUDY OF PHASE-CHANGE AROUND A ROTATING ISOTHERMAL CYLINDER

Melting around a rotating vertical cylinder heated at constant tempera ture is being studied numerically. The problem is examined for a phase change material of constant thermal properties, initially at the fusi on temperature, confined between two horizontal fixed adiabatic planes . Natural convection effects are left aside to study the coupling betw een melting and the growth of Taylor vortices in a cavity with continu ously decreasing aspect and annular ratios. The governing equations fo r axisymmetric flow in the melt region are solved numerically, for sma ll Stefan numbers, using body-fitted grids. As a consequence of the fi nite cavity length, the growth of the cells is a smooth process. For s mall Prandtl numbers, melting and rotation are uncoupled and the inter face remains straight, but the number of cells found in the melt at an y given time is generally different from that found in an identical ca vity of fixed geometry. For a Prandtl number of order one, there is a strong coupling between melting and the Taylor vortices and the interf ace becomes highly distorted.