Decoupling transport and reaction kinetics effects on open thermochemical heat discharging performance
File(s)
Published version
Author(s)
Li, Wei
Zeng, Min
Wang, Qiuwang
Markides, Christos N
Type
Journal Article
Abstract
Salt hydrate-based thermochemical energy storage (TCES) represents a promising pathway toward a sustainable energy future. A numerical model incorporating a multiscale dual-porosity framework that couples external transport phenomena with intra-particle diffusion is developed and experimentally validated in this article. Based on this, the heat-discharge characteristics of composite thermochemical material in a lab-scale fixed-bed reactor are numerically analyzed. The decoupling analysis, combining the unified dimensionless framework, examines the independent effect of heat/mass transport and reaction kinetics for this open TCES reactor. Results manifest that under the specified experimental conditions, the lab-scale reactor maintains an output temperature exceeding 35℃ for 70.2% of the total discharge duration. The variations in dimensionless parameters, such as mass transfer Péclet number (Pem) and Nusselt number (Nu), fundamentally confirm the intensification of heat-mass transport and reaction kinetics with increasing Reynolds number (Re) and relative humidity (RH). For the scaled-up reaction bed, elevating the inlet RH from 55% to 95% amplifies the temperature lift (Tup) from 19.6℃ to 30.5℃; while beyond a threshold of around 1200, further increases in Re induce a slight drop in Tup. The output power, however, increases with both RH and Re, reaching a maximum value of 2830 W within the parameter range studied. Coordinated matching of reaction kinetics with the heat-mass transfer capabilities is practically required. Relative to the intrinsic gas–solid reaction, the primary pathway for enhancing discharge performance of a pilot-scale TCES reactor is the mitigation of transport resistances across both microscopic and macroscopic scales. This work provides theoretical guidance for the design and optimization of next-generation reactors for efficient salt hydrate-based TCES.
Date Issued
2026-10-01
Date Acceptance
2026-06-03
Citation
Energy Conversion and Management, 2026, 365 (1)
ISSN
0196-8904
Publisher
Elsevier
Journal / Book Title
Energy Conversion and Management
Volume
365
Issue
1
Copyright Statement
© 2026 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
License URL
Identifier
10.1016/j.sbi.2026.103309
Publication Status
Published
Article Number
121754
Date Publish Online
2026-06-06