الفهرس 
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Abstract
This research was carried out to study the phenomenon of the moving boundary problems including phase change due to heat transfer (melting-solidification). This phenomenon has appeared in many engineering applications like metal casting and growth of pure crystals from metals and solutions, steel industry, glass industry . Other applications include nuclear reactor safety, underground burial of radioactive wastes, underground coal gasification, ablation, spacecraft thermal control, freezing of moist soil and thawing of frozen ground, latent heat of fusion energy storage, ….etc.
The study of the moving boundary problem including phase change due to heat transfer has been carried out here by two different methods. The first method is experimental one, where a test rig has been designed and constructed to study this phenomenon on the melting process of the paraffin wax. Experimental runs were performed for different temperatures of the heating source ( 70 c* , 75c* , 80 c* ) . The temperature distribution in both liquid and solid phases has been measured. Also, the position of the front interface and its propagation have been determined .
The second method was a numerical one, where a mathematical model has been developed based on the coupling of equations that govern the phenomenon . The finite element method was used to develop this model to solve the transient analysis of a two-dimensional problem . The results obtained from the model has been compared with those obtained from the experiments. Also, the model has been verified through the comparison of results with those available in the existing literatures. from the findings reported in this thesis, it can be concluded that :
1.The transient temperature distribution through the test material during the phase change process is obtained as example.
2.The rate of melting for the paraffin was and the rate of ice formation are obtained as examples.
3.The progressive configuration of melting /solidification front is predicted.
4.The achievements reported in the present analysis show that the model is a good mean to predict the behavior of the moving boundary problem.
5.The code has overcome the limitations and shortages of many previous models like ; irregular boundaries, [practical boundary conditions and inhomogeneous materials.
6.The meting process of the paraffin is dependent upon the temperature of the heated side, the thermophysical properties, The dimentions of the test section.