A device for studying the chemical reactivity of condensed phase materials under concentrated solar irradiation has been designed and tested. Heating and cooling rates as well as stagnation temperatures have been calculated and verified experimentally. A key assumption for modelling was that radiation is the prevailing heat transfer mode. Calculated temperatures and those measured by modified pyrometry agree well. The results show that sample temperatures of 2000 K can be reached with heating rates up to 500 Ks−1. Non-forced cooling to ambient occurs with an average rate of about 60 Ks−1. Forced cooling, with calculated rates of 4000 Ks−1, can be achieved with the built-in quench device. Reactivity studies have been initiated on iron oxides and manganese oxide, respectively. The results have shown that chemical analysis of the solid residue provides information for typical reaction times in the range of minutes. On-line gas phase analysis by mass spectrometry has been used to monitor reactions with typical reaction times in the range of several seconds.

Issue Section:
Technical Papers
Keywords:
solar energy concentrators, solar heating, chemical reactions, sunlight, heat transfer, thermal analysis
Topics:
Irradiation (Radiation exposure), Radiation (Physics), Solar energy, Solar radiation, Temperature, High temperature, Cooling, Heating, Iron, Heat transfer, Density
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