Experimental results of gradual porosity volumetric air receivers with wire meshes

Central Receiver Systems with volumetric receiver technology has emerged as a scheme that could increase receiver and power block efficiencies. Among other choices, volumetric receivers made of metallic wire meshes are a promising technology that allows different designs and configurations. This paper details experimental work carried out on gradual porosity absorbers with the aim of promoting the basic principle of volumetric absorbers. In order to draw preliminary conclusions on the technology, a new lab-scale test bed of 1 kW was designed and used. As the absorber material, six commercial metallic wire mesh screens, of 310-alloy, with different geometrical and optical properties were selected with the constraint of finding pairs with similar porosities and different mesh properties. The thickness of each absorber was optimized in order to reduce the material needed to achieve complete absorption of the incident radiation. Moreover, pieces of two reference absorbers -TSA and SOLAIR-were tested. The concept shows potential for improving, or at least matching, the performance of the baseline absorbers (TSA and SOLAIR).