Study of an Internal Combustion Engine Fueled Partially with Green Hydrogen via the Recovery of its Exhaust Gases

In an internal combustion engine, approximately two-thirds of the energy contained in the fuel is converted into heat, which is a loss that engineers are currently seeking to recover to reduce consumption. It is striking to note that only 30% of the energy contained in the fuel is used to propel a vehicle, while the rest is dissipated as heat through the cooling system and primarily through the exhaust, which wastes over approximately 35% of the initial energy. Rather than simply heating the atmosphere, motor engineers and equipment manufacturers are working on systems capable of harnessing a portion of this lost energy. This is the major challenge of the internal combustion engine, and several manufacturers are seeking solutions for energy savings and reducing environmental impact. With this in mind, we propose to conduct a study that addresses at least one significant challenge: how to recover this wasted thermal energy and convert it into mechanical energy through cogeneration. Several solutions are possible, but our choice has focused on Stirling engines, which have demonstrated better efficiency compared to combustion engines and theoretically approach the efficiency of turbines. Implementing such a system is challenging, requiring highly specific components and a substantial investment. Therefore, our research is aimed at a close collaboration with the LAMIH laboratory (UMR CNRS 8201) at the Hauts-de-France Polytechnic University in Valenciennes, France, which is currently setting up a significant installation to meet these objectives. For the current state of progress, we have first results after making a performance comparison of 12 cases of mixture at the inlet of the internal combustion engine. These first results show us that 65% of unleaded 98 and 35% of HHO mixture has the best performance.