文章基本信息

标题：Studies on Paraffin-Graphite-Cu PCM Composites for Solar Thermal Storage Applications
本地全文：下载
作者：Kavitha. K ; Arumugam. S
期刊名称：International Journal of Innovative Research in Science, Engineering and Technology
印刷版ISSN：2347-6710
电子版ISSN：2319-8753
出版年度：2015
期号：ICMEET
页码：393
出版社：S&S Publications
摘要：In this paper an experimental investigation on the thermal storage capacity for a typical compositemixture of paraffin- Graphite- Cu PCM composite has been studied. Paraffin wax was used as the base phase changematerial (PCM) and the paraffin has been mixed with Cu turnings in different ratios 10, 50, 70 and 90 weightpercentages and considered as a composite. The thermal charge and discharge capacities of the paraffin- coppercomposite were tested and reported. The Paraffin copper PCM composite was found to have higher heat transfercapacity when compared to pure paraffin as PCM material. The heat charge and discharge performance of the Paraffinwas found to be high, when the Cu turnings were mixed with paraffin in a smaller ratio of 10 weight percentage whencompared with other weight percentage mixtures of copper. The shiny black colour nature of graphite has beenconsidered to provide a better absorption. The paraffin-Cu composite mixture was studied for different weightpercentage 10, 20, and 30 mixture of Graphite powder. It was found that 20 weight percentage mixture of the graphitewith paraffin-Cu had considerable better heat energy storage potential because of its expected good heat transferproperty and the results have been presented. These composite (paraffin- Graphite- Cu) sample were encapsulated inheat exchanger pipe of .02m diameter sealed at both ends of length 0.3m were subjected to thermal charging anddischarging capabilities. From the observation it is noted that heat exchanger pipes with the PCM composites havehigher rate of rise of temperature of 14.7 X 10-3 C/s, while charging the PCM composite. When compared with thecharging performance of pure paraffin, the rate of rise of temperature for the pure paraffin is known to be 6.389 X 10-3C/s. So the thermal charging time gets enhanced to more than double while using the PCM-composite as the PCMmaterial for thermal energy storage instead of pure paraffin alone. The rate of fall of temperature of the pure paraffinwhile discharging was 1.94X10-3C/s which was less than the rate of fall of temperature of the best composite4.167X10-3C/s. A best composition of PCM composite has been identified from the present study. The thermophysicalproperties of the paraffin and paraffin-Graphite-Cu composite are determined through the differential scanningcalorimeter (DSC) analysis. Further study is in process to use the PCM-composite in solar water heating application insolar thermal storage utilities.
关键词：PCMs; Copper turnings; Latent thermal energy storage; Heat transfer; Graphite powder; DSC