Structural Design And Numerical Simulation For A High-temperature Solid-liquid Phase Change Thermal Energy Storage Container

The high temperature solid-liquid phase change thermal energy storage container can combine with alkali metal thermal-electricity direct switch technology and form regenerative alkali metal thermal-electricity direct switch device, it can be used in the diving device under water and serves as motive force source on the spacecraft. So the device is of importance to under -water homework platform,under-water quiet type diving-device and technical development of power of the aircraft.The heat-conduction questions with phase-change exist in the actual project widely, such as liquid metal solidification in casting, high temperature plastic melting-body cooling and solidifying into making-piece, solidification and melting of the welding rod in the course of casting, and water solidifying into ice. It is characteristic of uncertainty and movement of the phase-change interface and the release or absorption of the latent heat in position of the phase-change interface, this kind of the question is also called the moving border question.Key question in the study of TES device is the release or absorption of the latent heat during the course of phase-change in PCM container. Owing to the constantly moving phase-change interface during the course of phase-change, the question possess the characteristics of the non-linear one. Besides a few simple situations, the accuracy solution of this kind of the question is solved difficultly. Generally speaking, the slightly complicated situations can only adopt the numerical method to solve.The high temperature solid-liquid phase change thermal energy storage container is an important part of regenerative alkali metal thermal-electricity direct converter in that the performance of the whole system is affected significantly by the heat transfer character of high-temperature phase change canister. This text make structure -designing for TES device according torequirement at first, choose the Fluorine lithium as the phase-change material and then the conjugating heat transfer mathematical model of the high-temperature phase change canister is established with the enthalpy method with numerial caculatation.we can get the detailed temperature profile within TES device, distribution of the thermal current density , movement law of phase-change interface, PCM maximum temperature and great difference in temperature, melt - solidification time cycle, and variety of PCM melting share within one cycle by thermal analysis ,we can also understand influence on storing-releasing energy course of PCM physical property and external border terms, know the movement law of the phase-change interface, confirm design parameters such as quantity of the energy storage medium, total time during the course of the phase-change; at the same time method of the structure design and super operating conditions avail to practical application and economy are aquired by comparing and analyzing performance of three kinds of the heating way Based on thermal analysis the thermal stress analyzing is executed , intensity checking prove TES device(PCM container wall and outer cover mainly)to be rational,safe and steady enough . We find out the reason and position that may flaw through the result of computational analysis at the same time, put forward the improving suggestion, which thus offer the reliable basis for the thing that the design of the products is improved and have great reference value in the project uses.Finally for investigating natural convection influence on the course of the solid-liquid phase-change heat transfer,the conjugating heat transfer mathematical model of high-temperature phase change canister with the natural convection is established with the amending equivalent heat capacity method by two kinds of the method (equivalent heat capacity method dealing with phase-change latent heat, varying viscous coefficient dealing with solid and fluid viscosity ),thus solid- liquid phase PCM,rib wall, heater, insulating material and outer cover can be on whole asks and solved in union. In order to solve the problems...