Abstract

A multi-tubular solar thermochemical cavity reactor is proposed and the tubular array optimized. The optimized reactor design aims at operating under different temperatures and carrying out different kinds of thermochemical reactions. The radiation entering the receptacle comes from a solar concentrating system and the reactor consists of a cubic receptacle made of woven graphite, housing nine 2.54 cm diameter tungsten tubes. A model is developed and implemented considering high-temperature radiative transfer at steady state. The temperature distribution within the cavity surfaces is determined by employing a hybrid Monte Carlo-Finite Volume approach. Optimal tube distributions are explored by using a custom-made stochastic, multi-parameter, optimization algorithm. In this way, multiple global maxima are determined. Patterns among all possible optimal tube distributions within the cavity are obtained for different scenarios, by maximizing average tube temperature. From this study, practical guidelines are obtained for future application in the design of solar cavity reactors and more specifically, on the layout of multi tubular arrays to optimize radiative heat transfer.