Experimental determination of the effective thermal capacity function and other thermal properties for various phase change materials using the thermal delay method

Kravvaritis, ED; Antonopoulos, KA; Tzivanidis, C

dc.contributor.author	Kravvaritis, ED	en
dc.contributor.author	Antonopoulos, KA	en
dc.contributor.author	Tzivanidis, C	en
dc.date.accessioned	2014-03-01T01:35:40Z
dc.date.available	2014-03-01T01:35:40Z
dc.date.issued	2011	en
dc.identifier.issn	0306-2619	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/21155
dc.subject	Phase change materials	en
dc.subject	PCM properties measurement	en
dc.subject	Thermal delay method	en
dc.subject	Effective thermal capacity	en
dc.subject.classification	Energy & Fuels	en
dc.subject.classification	Engineering, Chemical	en
dc.subject.other	T-HISTORY METHOD	en
dc.subject.other	LATENT-HEAT	en
dc.subject.other	TEMPERATURE CURVES	en
dc.subject.other	ENTHALPY	en
dc.subject.other	FUSION	en
dc.subject.other	IMPROVEMENT	en
dc.subject.other	ACCURACY	en
dc.subject.other	STORAGE	en
dc.title	Experimental determination of the effective thermal capacity function and other thermal properties for various phase change materials using the thermal delay method	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.apenergy.2011.05.032	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.apenergy.2011.05.032	en
heal.language	English	en
heal.publicationDate	2011	en
heal.abstract	The recently presented thermal delay method is an improved version of the well-known T-history method, which is widely used for thermal properties measurement of phase change materials (PCM). The most important difference between the thermal delay and the T-history methods is that the former is based on the use of thermal delay (i.e. temperature difference) between PCM and a reference fluid at any specified time while the latter makes use of their time delay at any specified temperature. Although the thermal delay method has been documented in our previous publication, measurements are performed of the known and indisputable values of ethyl alcohol thermal capacity and the latent heat of the double distilled water (WFI), which confirm the accuracy of the method. Additional comparisons with values provided by PCM producing companies show disagreements lower than 1.7%. The main volume of measurements of the present study includes the following thermal properties of various practically interesting PCM: (a) the temperatures at the ends of the two-phase region; (b) the liquid and solid PCM thermal capacities; (c) the phase change heat; (d) the heat storage capacity during any specified temperature range; and (e) the effective thermal capacity function, which is a very important and useful property for practical applications. The above function is provided for each one of the PCM examined in the form of diagrams, as well as in the form of analytical expressions derived by curve fitting to the processed experimental values. All measurements were repeated 20 times and the results were averaged in order to minimize errors from accidental incidents. (C) 2011 Elsevier Ltd. All rights reserved.	en
heal.publisher	ELSEVIER SCI LTD	en
heal.journalName	APPLIED ENERGY	en
dc.identifier.doi	10.1016/j.apenergy.2011.05.032	en
dc.identifier.isi	ISI:000295387200021	en
dc.identifier.volume	88	en
dc.identifier.issue	12	en
dc.identifier.spage	4459	en
dc.identifier.epage	4469	en