Optimization of recuperative burners for industrial kilns through CFD simulation

An optimization of the shape of a recuperative burner for industrial furnaces for tiles production is presented. The aim of the study is the maximization of the energy recovery from exhaust gas across a heat exchanger in order to pre-heat the combustion air. The study is carried out by means of CFD simulations. Eleven geometric parameters have been chosen and varied individually in an introductory sensitivity analysis. Useful information on the parameters influence have been thus obtained. Due to the large grid size and computing times, a direct optimization has been deemed unfeasible for our purpose. In its place, a fine tuning of the solution has been achieved by investigating the parameters interactions and finding a rather linear superposition of the effects. A reduction of the burner fuel consumption of almost 5% has been attained without affecting the markers of the product firing quality, such as the temperature profile on the tiles floor along the kiln room.