Volume 5: Innovative Solutions for Energy Transitions: Part IV

Investigation of an Innovative Three-Phase Thermochemical Reactor for Building’s Application Cheng Zeng, Shuli Liu, Ashish Shukla, Liu Yang, Xiaojing Han

Abstract

Increasing the share of renewable energy in buildings sector is essential. While the dynamic nature of the renewables is an obstacle for improving its efficiency. In this context, thermal energy storage technologies are to store the renewables and supply it to meet building’s demand. Thermochemical energy storage stands out in advantages including high energy storage density and low thermal loss. However, for a thermochemical energy storage system, the thermochemical reactor is critical. To tackle drawbacks of the reactor, this paper proposes an innovative three-phase thermochemical reactor and investigates its performance through an experimentally validated numerical model. The reactor is integrated with fins and air gaps to enhance heat and mass transfer. Key parameters and the related heat and mass transfer efficiency of the reactor in both charging and discharging processes have been investigated. According to the analysis, the integration of fins has increased the reactor performance by 129% in charging and by 77% for COP in discharging. The effect of fin pitch has been examined and the results show that reducing the fin pitch can increase the reactor performance by up to 14% in charging and 7.5% in discharging. However, the enhancement is not sensitive for fin pitch lower than 30 mm. Additionally, increase the gap size can enhance the charging performance but may reduce discharging efficiency and the optimal gap size range is 3 mm to 5 mm.

Keywords thermochemical energy storage, reactor, heat and mass transfer enhancement, reactor performance analysis