Thermal and optical analysis of an air-cooled camera-target system for concentrated solar flux evaluation

Accurate and rapid evaluation of concentrated solar flux remains challenging due to the complexities of conventional water-cooled camera-target systems, which hinder experimental and operational flexibility. This study aims to address these limitations by employing a novel air-cooled target system. A system comprising an instrumented, sandblasted aluminum target, a Gardon gauge, and a CCD camera was designed and validated in a solar furnace. Our methodology introduces an optical model to characterize the target, superposing Lambertian and Gaussian specular components. Thermographic measurements are used to resolve spatial and temporal temperature distributions. It is found that sandblasted aluminum exhibits high Lambertianity (87%), validating its use as a target. The air-cooled system, employing a diffuse back-and-front air-cooling configuration, successfully manages thermal loads, keeping the target plate below 284 ° C, without structural degradation, for peak fluxes up to 2 . 3 MW m − 2 . The estimated accuracies for the flux and total radiative power evaluations are 3.25% and 1.79%, respectively. A physically based transient thermal model, validated against thermographic data, is used to investigate hotspot formation and to determine cooling requirements for higher thermal loads. This work’s key outcome is the successful validation of a robust, air-cooled, fast-deployment solar flux measurement system that offers a simpler, faster setup than water-cooled alternatives and eliminates associated leakage issues. • Air-cooled camera-target method developed for concentrated flux evaluation. • Combined diffuse–Gaussian reflection model shows excellent fit to reflection profiles. • Thermal model validated against thermography allows operational limits assessment. • Air cooling provides reliable evaluation capabilities with an easier, faster setup. • Experimental–numerical approach provides guidelines for enhanced cooling control.