Design of thermoelectric generator for waste heat recovery from marine internal combustion engines

Abstract

Large amounts of energy are released into the environment by modern ships. More precisely, the exhaust gases from internal combustion engines (ICE) on commercial and passenger ships discharge enormous amounts of thermal energy at high temperatures into the environment. Utilizing thermoelectric generator devices, which can transform thermal energy into electrical energy when there is a sufficient temperature difference, is a viable way to recover some of this energy. The purpose of this work is to suggest a thermoelectric generator for recovering waste heat energy from marine ICE exhaust gases. The proposed thermoelectric generator uses the outside surface of the ICE manifold as the hot side of the thermoelectric module, while the cold side is maintained at a low temperature through a heat sink and room temperature water flow. The target of this work is to design this thermoelectric generator and recognize the configuration that generates the maximum electric power. The analysis and design are performed with the use of modeling and simulation, while commercial software is employed to study the 3-dimensional coupled fluid flow and heat transfer at steady state conditions. A sensitivity analysis is carried out in order to identify the parameters with the highest contribution to the produced power. Besides to a full factorial optimization analysis, the more efficient Latin hypercube sampling is used. The analysis results demonstrates that substantial energy of the exhaust gases can be transformed into electric power. This is achieved with a device that is able to create the highest temperature difference between the two sides of the thermoelectric module with the use of an optimized water cooled heatsink.