Simultaneous measurement of irradiation,temperature and reflectivity on hot irradiated surfaces

Conversion of solar energy into chemical fuels has been a field of intense research for many years. It is usually attempted as a thermochemical reaction under highly concentrated solar irradiation, e.g. in a solar furnace. Special interest has been addressed to the question of whether concentrated light drives the reaction differently than heat. One effect of irradiation might be a decrease of the reaction temperature. To observe such an influence it is important to monitor the chemical process and the surface temperature of the sample under irradiation. In this paper we propose a method to measure the temperature, the irradiation and the reflectivity/emissivity distribution on an irradiated sample surface simultaneously. We first outline the computational background of the method and discuss its accuracy. We then report on laboratory measurements as well as on experiments performed in a solar furnace.