Geometric Optimization of a CeO2-Based Solar Thermochemical Reactor for Hydrogen Production: Temperature Distribution Analysis under 2 kW Concentrated Solar Power
Annotatsiya
This study presents the geometric optimization of a CeO2-based solar thermochemical reactor intended for hydrogen production, using temperature distribution analysis under concentrated solar power conditions. The investigation was carried out entirely through numerical modeling using the COMSOL Multiphysics software, assuming a concentrator input power of 2 kW. The reactor body was designed with a stainless-steel exterior, while aluminum oxide (Al2O3) was selected as the internal insulating layer. Cerium oxide (CeO2) was employed as a porous reactive medium to facilitate a two-step redox thermochemical cycle. A three-dimensional cylindrical model of 1 mol CeO2 was developed to evaluate the thermal performance under varying porosity levels (ε = 0.1–0.9) and different cylindrical geometries with equal volumes. The simulation results revealed that at a porosity of ε = 0.7, the desired endothermic operating temperature was distributed most uniformly within a CeO2 volume of 50 mm diameter and 20 mm thickness. Based on the temperature field distributions and effective heat transfer conditions, the reactor’s geometrical parameters were optimized. The final design includes a cylindrical body with a 220 mm diameter and 140 mm length, a quartz window of 200 mm diameter and 6 mm thickness, a 20 mm cooling channel for water circulation, and an internal insulating layer of aluminum oxide (Al2O3) with a thickness of 100–120 mm. Furthermore, the dimensions of the light-receiving conical section were determined as 50 mm for the small diameter and 152 mm for the large diameter.