Estudo numérico da transferência de calor em trocadores de calor casco e tubos

Abstract

The goal of the present work is simulation of heat transfer in a shell and tube heat exchanger. Heat exchangers are thermal machines of high responsibility in power plants, approximately 90% of heat exchangers are shell and tube models, due to well-established design and manufacturing procedures. The system involving fluid flow and heat transfer is analyzed using Computational Fluid Dynamics. The simulation were performed on two geometries; The first, the shell and tube heat exchanger did not have baffles; in the second, baffles in the same geometry were added. The simulation of the first geometry was used to compare the results and evaluate the parameters used, but the second, represents a geometry with the main components present in shell and tube heat exchangers. OpenFOAM has been used for the simulations as numerical tool, modeling the problem as transient. The k-epsilon and LES Large-Eddy Simulation turbulence models were also used. The results of the study show the temperature and velocity contours, as the turbulence geometry and modeling, performing a comparison of the heat transfer rate. The values of the turbulence models are similar to each other and to a similar study. Verified a 22% increase in heat transfer rate due to baffles included in the geometry.