The assumption we used to approximate our solution will be based on the heat transfer between control volumes only. Our problem that is being considered in this research will be about the solidification of tubular ice in three dimensions. We will only study on the freezing surface which ammonia will be around the ice making tube and ice will be formed from the edge of surface as shown in Figure 3.11 and 3.12. We will concern only the solidification process where liquid water will freeze into ice with these assumptions as following.