Solar convective furnace for heat treatment of aluminium

Abstract

Heat treatment of metal is an energy intensive process. Currently direct electrical energy is employed for this purpose. The harnessed heat using concentrated solar thermal technology can be employed for processing of metal, like, annealing of Aluminium. This paper presents a technology that uses solar energy as fuel and converts the harnessed heat for this purpose. An existing heat treatment furnace is scaled down and retrofitted to demonstrate solar convective heating concept. Air-flow velocity measurements in furnace side-duct are performed using laser Doppler velocimeter (LDV) along the centerline of injection circular nozzle. Comparison with the reported impinging jet profiles shows that air-flow in the side-duct is asymmetric. Computational fluid dynamics (CFD) approach based on different turbulent models is used for air-flow analysis. The selected CFD approach is validated by comparing measured velocities. Validated CFD tool is used for details flow analysis in the furnace. Detailed analysis revealed the formation of a vortex structure under the heart region, which is expected to influence the metal processing quality.