Optimization Study Of Heat Storage Perrormance Of Shell And Tube Phase Change Thermal Storage

Now, coal and oil are mainly energy in life and production, but with the depletion of fossilenergy and the environmental pollution problems generated in using process have becomeincreasingly prominent, Energy-saving and environmental protection has become the mostcompelling issues, development and utilization of new energy sources is a priority. Solar energyas a clean and renewable energy, and has a broad application space, applied to the solar heatpump system can effectively alleviate the problem of rising energy consumption of daily life.Solar energy density is low and intermittent, generation of heat storage technology has solved thecontradiction between the solar energy supply and utilization.Shell and tube phase change accumulator is the most common thermal storage apparatus, butfor a simple shell and tube phase change heat storage, due to the very low coefficient of thermalconductivity of the phase change material, the heat exchanger performance is poor and can notachieve the purpose of fast endothermic and exothermic, we must adopt effective measures toimprove the melting rate of the phase change material.This paper introduces a new kind of shell and tube phase change heat storage device withstraight longitudinal ribs on the inner tube, having established the physical and mathematicalmodel, and numerical simulation to research the melting law of phase transition.Firstly, the subject established a simple pipe model without fin，numerical simulation at thefirst boundary condition, and analyzed the movement law of solid-liquid interface, temperature distribution and the of the melting process, the influence of natural convection to the melting, aswell as the existence of natural convection accelerated the speed of melting.Secondly, we added straight fins in the pipe, established the physical and mathematicalmodel. After the numerical simulation, we found that the melting time greatly shorten, additionof fins. Having compared the solid-liquid surface and velocity distribution with the modelwithout fin. Then we performed9set of analog of different fins setting, respectively analyzed thecircumferential rib number, fin thickness, and rib distribution factors on the influence of melting.Then base on the question of pipe bottom melt slow in melting process, two models as compositefins and the symmetrical distribution model are proposed. Both methods are effective to solvethis problem.Finally, this paper describes the heat pipe heat accumulator model, established physical andmathematical model to simulate the melting law of the phase change material. Compared melttime with fin model, heat pipe superconductivity can effectively enhance the heat exchanger ofregenerator. However, compared with the fin model③and asymmetric model B, the effect isquite. The heat pipe heat transfer enhancement effect is very good, but the key is how to layout.