Theoretical Predictions for Latent Heats and Phase-Change Temperatures of Polycrystalline PCMs

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21110%2F17%3A00312616" target="_blank" >RIV/68407700:21110/17:00312616 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1063/1.4994506" target="_blank" >http://dx.doi.org/10.1063/1.4994506</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1063/1.4994506" target="_blank" >10.1063/1.4994506</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Theoretical Predictions for Latent Heats and Phase-Change Temperatures of Polycrystalline PCMs

Popis výsledku v původním jazyce

We had previously developed a microscopic approach from which it is possible to fit enthalpy jumps and heat capacity peaks of polycrystalline phase-change materials that consists of a large number of grains. It is also possible to determine the corresponding latent heat and phase-change temperature. These results are given in a form of sums over grain diameters that can be evaluated numerically. Therefore, their behavior and dependence on physical parameters are not susceptible to straightforward interpretations. Here we use the results to derive simple formulas for the maximum position (Tmax), height (H), and an asymmetry factor (α) of those heat capacity peaks that are very asymmetric. In addition, we express the phase-change temperature as a simple combination of Tmax, H, α, and the peak’s area. We apply our formulas to Rhubitherm 27 as an example PCM for which the heat capacity peak is so asymmetric that it has about 80 % of its total area below its maximum position.

Název v anglickém jazyce

Theoretical Predictions for Latent Heats and Phase-Change Temperatures of Polycrystalline PCMs

Popis výsledku anglicky

We had previously developed a microscopic approach from which it is possible to fit enthalpy jumps and heat capacity peaks of polycrystalline phase-change materials that consists of a large number of grains. It is also possible to determine the corresponding latent heat and phase-change temperature. These results are given in a form of sums over grain diameters that can be evaluated numerically. Therefore, their behavior and dependence on physical parameters are not susceptible to straightforward interpretations. Here we use the results to derive simple formulas for the maximum position (Tmax), height (H), and an asymmetry factor (α) of those heat capacity peaks that are very asymmetric. In addition, we express the phase-change temperature as a simple combination of Tmax, H, α, and the peak’s area. We apply our formulas to Rhubitherm 27 as an example PCM for which the heat capacity peak is so asymmetric that it has about 80 % of its total area below its maximum position.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20101 - Civil engineering

Projekt

<a href="/cs/project/GBP105%2F12%2FG059" target="_blank" >GBP105/12/G059: Kumulativní časově závislé procesy ve stavebních materiálech a konstrukcích</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

THERMOPHYSICS 2017: 22nd International Meeting of Thermophysics 2017 and 4th Meeting of EnRe 2017

ISBN

978-0-7354-1546-1

ISSN

—

e-ISSN

1551-7616

Počet stran výsledku

5

Strana od-do

—

Název nakladatele

American Institute of Physic AIP

Místo vydání

Santa Fe

Místo konání akce

Těrchová

Datum konání akce

12. 9. 2017

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000426600400031