| Abstrakt: |
Concentrated solar power plants have become an attractive option for generating power by providing the ability to generate heat at high temperatures. One of the most important problems of power generation by solar energy is the lack of permanent access to solar radiation and the lack of coordination between production time and consumption time. The use of thermochemical storage with advantages such as wide operating temperature range and high energy density is one of the suitable options to overcome this problem. In TCHS, the received heat is stored in the form of chemical energy by an exothermic reaction and then this energy is released in an exothermic reverse reaction. Reversible REDOX reactions of metal oxides have attracted much interest due to the gas–solid reaction and the fact that air can act as both a heat transfer fluid and a reactant. Among metal oxides, cobalt oxide is a good choice due to its suitable reaction temperature, high reaction enthalpy, as well as good cycle stability, and reasonable price. In this research, a two-dimensional simulation of a thermochemical energy storage reactor using Co3O4/CoO as a redox pair in full charge and discharge cycle has been performed using COMSOL software. The effect of important operational and geometric parameters [inlet airflow, porosity, number of cells in honeycomb structure (CPSI), diameter to reactor length ratio, and the conical reactor evaluation] to reduce charging time has been investigated. Using the three-level Box–Behnken experimental design, the sensitivity of charge time to four effective factors was investigated. The results showed that the most important factor influencing charging time is the inlet airflow. However, by increasing the inlet airflow, the discharge time, as well as the maximum outlet temperature, decreases. Therefore, the optimal conditions for obtaining the minimum charging time were determined by excluding the effect of airflow. [ABSTRACT FROM AUTHOR] |
