Rheological Behavior of Phase Change Slurries for Thermal Energy Applications.
Langmuir
; 39(1): 129-141, 2023 Jan 10.
Article
em En
| MEDLINE
| ID: mdl-36574262
ABSTRACT
Phase change materials that leverage the latent heat of solid-liquid transition have many applications in thermal energy transport and storage. When employed as particles within a carrier fluid, the resulting phase change slurries (PCSs) could outperform present-day single-phase working fluidsâprovided that viscous losses can be minimized. This work investigates the rheological behavior of encapsulated and nonencapsulated phase change slurries (PCSs) for applicability in flowing thermal energy systems. The physical and thermal properties of the PCS candidates, along with their rheological behavior, are investigated below and above their phase transition points at shear rates of 1-300 s-1, temperatures of 20-80 °C, and concentrations of 15-37.5 wt %. The effect of shell robustness and melting on local shear thickening and global shear thinning is discussed, followed by an analysis of the required pumping power. A hysteresis analysis is performed to test the transient response of the PCS under a range of shear rates. We assess the complex viscoelastic behavior by employing oscillatory flow tests and by delineating the flow indicesâflow consistency index (K) and flow behavior index (n). We identify a viscosity limit of 0.1 Pa·s for optimal thermal performance in high-flow applications such as renewable geothermal energy.
Texto completo:
1
Base de dados:
MEDLINE
Idioma:
En
Revista:
Langmuir
Assunto da revista:
QUIMICA
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Canadá