2The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta GA, U.S.A
3Department of Material Science and Engineering, Stanford University, Stanford CA, U.S.A.
4School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta GA, U.S.A.
5The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta GA, U.S.A. School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta GA, U.S.A.
Abstract
A numerical model is developed to analyze a new solar thermochemical reactor using liquid metal as a heat transfer fluid. Reaction kinetics for both reduction and oxidation in twostep redox cycles using a metal oxide are modeled by fitting to experimental data. The transient model includes the heat and mass transfer and reaction kinetics for an analysis of the efficiency and to elucidate limiting factors. The reactor can achieve an efficiency of 20% for the conversion of thermal to chemical energy for our base design. For this design, the removal of oxygen during the reduction step was determined to be the bottleneck to achieve a higher efficiency. In a sensitivity analysis, the optimal reaction temperature can be found considering the trade-off between fast reaction kinetics and materials compatibility.
