Study On The Flow Field On The Phase-change Heat Transfer

. According to the related materials from 《BP world energy statistics2007)), World Energy Council, the resource reserve-production ratio of the main non-renewable energy resource based on production2006, respectively, coal147、oil42、gas63.So the study on energy-saving technology is imminent. Heat storage technology as an important component of the energy-saving technology, Not only in the use of traditional and new energy sources is of great significance, but also in such areas as industrial waste heat recovery have a broad range of applications.Through studies the existing phase change theory, this paper found that the storage/release theory pays much attention to the phenomenon, but there is little research on the mechanism of its occurrence. Based on the phase change theory, this paper analysis the influence of natural convection on factors, such as RT@20of boundary conditions, initial conditions, and thermal parameters by the numbers. Taking fulent6.3as the platform, using Boussinesq hypothesis, porous medium assumption, can realize double equation model, the enthalpy method melting model theory of emergence and development of phase change melting process flow simulation. Using the field synergy theory on the flow field and temperature field synergy principle, field effect on heat transfer in the melting process was described, providing guidance for optimization design of rib Main conclusions were as follows:Single heat source conditions:at the condition of heat from the lateral part, the natural convection occurs in an earlier. In the early melting, the way of heat transfer depends is conduction. As the melting process continues, the effects of natural convection are enhanced. But the stagnation zone which increases thermal resistance gradually formed on the side wall. At the condition of heat from the bottom:the natural convection occurs in the late. The location of natural convection occurred in the liquid and paste area junction. Development experience instability in the natural convection developed into a relatively stable development. Its heat exchanging effect is stronger than the convection heat transfer which the heat quantity from the lateral part.Multiple heat source conditions:Natural convection located on the lateral part will put the PCMs which are on the top or the bottom in motion, produce or earlier to produce natural convection, which enhances heat transfer. As the temperature of PCMs rose by top or bottom heat source, the stagnation zone which located on lateral part formulated earlier. Its Thermal resistance increased. The side heat transfer was affected. As the top or bottom heat source heating, the temperature of the side of the circulation raised, reduces the lateral side heat circulation and temperature, thereby reducing side effects of heat transfer.