An experimental investigation of the melting process in a rectangular enclosure

An experimental investigation of the melting process in the vicinity of a heated vertical wall in a rectangular enclosure is presented in this work. A flat-plate heat pipe was used to provide a uniform temperature source. The liquid flow patterns during the melting process were captured and the instantaneous marching of the liquid‐solid interface was presented. In addition, the temperature distributions in the phase change material were measured at the mid-plane as well as top and bottom walls of the enclosure. Three diAerent heat transfer regimes were identified during the melting process. The parametric domain covered the range of Ra=2.0210 6 ‐2.6110 7 , Ste Fo=0.001‐ 0.125 and Pr=804‐1055 while the critical Rayleigh number where the transition from the conduction to the convection regime occurs was found to be in the range of 7.869 10 6 ‐3.237 10 7 . It was found that the melt volume fraction and the time-averaged Nusselt number can be correlated by: V/Vo=4.73Fo 0.906 Ste 1.538 Ra 0.002 and Nu=0.0219Ra 0.387 Pr 0.0191 (H/d) 0.0621 respectively. # 1999 Elsevier Science Ltd. All rights reserved.