Preparation And Thermal Performance Study Of New Compound Phase Change Cool Storage Materials For Refrigerator

In this century, people are confronted with energy crisis and electricity shortagewhich have become the most significant problem. Energy storage technology is aneffective method to relieve the inconsistency of time, intensity and locations betweenthe supply and demand sides and its importance has been realized by more and morepeople. In recent years, the research and application of phase change cool storagetechnology is quite active, with the external cause of increasing attentions onenvironmental protection and energy conservation in most countries of the world and ofthe profit motive from the different price of electricity day and night, as well with theinternal cause of new growth point brought by the development of material science.However, cool storage technology has rarely been used in household refrigerators whichare commonly household electrical appliances, and of which the electricity consumptionwill grow day by day with the increase of usage amount. So it is imperative to use coolstorage technology in refrigerator to realize the energy saving.In this thesis, referring to the existing problems of the cold room in refrigerator andon the basis of available cool storage technology and common materials for thermalenergy storage, lots of selective analysis and plenty of experiments ultimately come to anew organic compound phase change cool storage material which is applicable to thecold room in refrigerator. The new cool storage material is composed of decyl alcoholand hexadecyl alcohol, in which the mass fraction of decyl alcohol is93%. Somethermodynamic parameters of it was measured by experiment including phase-transitiontemperature, phase-transition latent heat, cycling stability, expansion coefficient andspecific heat at constant pressure. The results of measurement demonstrate that thisphase change cool storage material has appropriate phase-transition temperature (0.2℃),large latent heat (152.8J/g). The material acts out fine thermal stability and goodthermodynamic properties after different solidification-melting cycles of200times,400times and600times.In order to improve the heat conductivity of the organic compound phase changecool storage material of decyl alcohol and hexadecyl alcohol, it was compounded withcopper foam with porosity of95%, hole density of20PPI, pore size of1mm. And thenthe phase-transition temperature, phase-transition latent heat, specific heat at constantpressure and the characteristics of the accumulation and release of the cooling capacity are also measured by experiments. The results show that, after adding copper foam, thecompound phase change cool storage material has little change of phase-transitiontemperature (1.0℃) which is also in the range of cool storage temperature of the coldroom in refrigerator. The heat conductivity and the uniformity of temperaturedistribution of the compound phase change cool storage material are greatly improvedunder the condition that the phase-transition latent heat per unit volume reduces a littlebit. Consequently, as a new compound phase change cool storage material, thecompound phase change cool storage material with copper foam could be used in thefield of cool storage for the cold room in refrigerator.