Estudo da influência da configuração das aletas em uma camisa de resfriamento de um reator CSTR sobre a perda de carga e comportamento dinâmico da temperatura

Abstract

Continuous Stirred Tank Reactors (CSTRs) are widely used in chemical processes, especially in exothermic reactions, due to their ability to promote mixing and efficient temperature control. To improve the performance in temperature control for exothermic reactions, extended surfaces, called fins, were introduced in the reactor design. These extended surfaces aim to increase the heat exchange area and, thus, improve the heat transfer rate by convection, providing a better response in controlling the temperature of the stirred tank. In this work, simulations were performed in Salome, Octave, and Ansys CFX, for a CSTR reactor with different fin configurations, of the flat type with rectangular, triangular, and triangular-parabolic geometric profiles, which surround the reactor externally, in order to analyze the influence of fin geometries on the pressure drop and temperature distribution inside the reactor. The difference between the configurations was observed in the results of the convective heat transfer rate and pressure drop. The triangular fins were found to be more effective, reducing the coolant flow rate more than the other configurations and presenting the lowest pressure drop, providing superior performance. Using the modeling results, a material cost was obtained, disregarding the equipment and machining prices in the analysis, considering only the cost of the stainless steel used in the modeling. It was found that increasing the heat exchange area by adding fins is effective, bringing benefits to the process. The fin configuration with a triangular profile proved to be the most advantageous for optimizing reactor temperature control.