Simulation And Experimental Research On Energy Storage Of New Composite Phase Change Materials Used In Building Envelope

Energy is the material basis for the human survival and development. With therapid economic development, energy supply and demand issues becoming moreprominent, as well as looking for new alternative energy and energy-saving technologyis also imperative. Building energy conservation is a new challenge faced by theconstruction industry development, and is one of the important topic for the futurearchitecture development. A new type of high efficiency and energy saving buildingwall which combined the phase change material with the traditional building materials,not only reducing the indoor temperature fluctuation, improving indoor thermal comfort,but also reducing the energy consumption of building air conditioning, so as to realizethe building energy efficiency.The FLUENT software is adopted to carry out numerical simulation for thetemperature distribution of the building envelope blending with phase change materials,the results was contrasted with the experimental data of other papers, the studyidentified that the experimental and numerical results are consistent, the relative errorkeeps in reasonable range. On this basis, using the method of numerical simulationanalysis compared with the experiment to study the phase change wall thickness andmaterial proportion, the influence of the phase change wallboard position distributionon energy storage process, the study shows that when the thickness is small, while thethermal resistance is small, but the content of phase change materials is less, thecorresponding decrease of the heat storage capacity, the thermal resistance increaseswhen the thickness is too large, will reduce the performance of phase change wall heattransfer, the leakage of phase change materials will happen, so we need seek the bestproportion of phase change materials. Through the analysis of optimization location ofphase change wallboard, when the phase change wallboard placed in the interior, theeffect of reducing internal wall temperature fluctuation is more obvious.In order to improve the heat conductivity of the fly ash composite phase changematerials in the previous study, it was compounded with copper foam. And then thephase-transition temperature, phase-transition latent heat are measured by experiments.The results show that, after adding copper foam, the compound phase change storagematerial has little change of phase-transition temperature (18.6℃) which is also in therange of the comfort temperature, the phase-transition latent heat is declined to149.3J/g. The wall inner surface temperature and space point temperature change curve of copperfoam composite phase change materials is measured by the method of experimental andsimulation, the adding of copper foam can significantly increase the coefficient ofthermal conductivity of composite materials, achieving the goal of building energyefficiency.