CFD Study of the Heat Exchange Process in an Energy Recovery System Applied to Low Displacement Diesel Engines

Abstract

Nowadays, there is a growing need to improve the performance of processes and systems in order to improve their efficiency, reduce operational costs, and reduce the impact on the environment. In this work, an energy recovery system based on thermoelectric is presented, which allows the residual energy of the exhaust gases to be converted into electrical energy through thermoelectric modules. The biggest challenge of this type of system is to make the recovered energy meaningful, so heat transfer processes play a fundamental role. In order to maximize the surface temperature, which will lead to an increase in recovered energy, the development of a methodology through CFD is proposed, using OpenFOAM® software, so that the surface energy is maximized. However, at the same time, it is guaranteed to minimize the heat drop inside the heat exchanger. Different geometries applied to the energetic recovery are studied in a SOKAN F300 diesel engine of small displacement, with which it has been possible to locate a geometry that guarantees the maximum recovery rate and a pressure drop of less than 300 Pa, so the gas backpressure Exhaust does not affect the performance of the thermal machine. The results obtained are validated experimentally, and deviations less than 5% are observed with the simulated results.