Title data
Delgado, Mónica ; Lázaro, Ana ; Biedenbach, Michael ; Gamisch, Sebastian ; Gschwander, Stefan ; Höhlein, Stephan ; König-Haagen, Andreas ; Brüggemann, Dieter:
Intercomparative tests on viscosity measurements of phase change materials.
In: Thermochimica Acta.
Vol. 668
(2018)
.
- pp. 159-168.
ISSN 0040-6031
DOI: https://doi.org/10.1016/j.tca.2018.08.017
Abstract in another language
Phase change materials (PCM) are capable of storing thermal energy within a small temperature range due to their high latent heat. When designing a thermal energy storage (TES) system with PCMs, besides the phase change enthalpy, thermal conductivity and density, viscosity based on temperature must be characterized to take into account natural convection. Taking advantage of the facilities of the different research groups working within an international network, a set of intercomparative tests were executed to determine the viscosity based on the temperature of two PCMs: octadecane and the commercial paraffin RT70 HC. Three laboratories have participated, which have used three different rheology equipments: two controlled stress rheometers, AR-G2 from TA Instruments and MCR 502 from Anton Paar and a translational rheometer, IMETER. The intercomparative tests were executed based on a starting methodology approach defined previously by some of the authors. The highest deviations were observed when temperature-controlled geometries or temperature hoods were not used at elevated test temperatures due to the temperature gradients within the sample, as consequence of the heat losses due to the room temperature. Consequently, special attention must be focused on the temperature control, since a uniform temperature throughout the sample should be guaranteed.
Further data
Item Type: | Article in a journal |
---|---|
Refereed: | Yes |
Keywords: | Viscosity; Rheology; Natural convection; Phase change materials; Round robin test |
Institutions of the University: | Faculties > Faculty of Engineering Science > Chair Engineering Thermodynamics and Transport Processes Faculties > Faculty of Engineering Science > Chair Engineering Thermodynamics and Transport Processes > Chair Engineering Thermodynamics and Transport Processes - Univ.-Prof. Dr.-Ing. Dieter Brüggemann Profile Fields > Emerging Fields > Energy Research and Energy Technology Research Institutions > Research Units > ZET - Zentrum für Energietechnik Faculties Faculties > Faculty of Engineering Science Profile Fields Profile Fields > Emerging Fields Research Institutions Research Institutions > Research Units |
Result of work at the UBT: | Yes |
DDC Subjects: | 600 Technology, medicine, applied sciences > 620 Engineering |
Date Deposited: | 27 Feb 2019 10:37 |
Last Modified: | 21 Oct 2022 06:49 |
URI: | https://eref.uni-bayreuth.de/id/eprint/47275 |