The analysis of the injection of hydrogen-oxygen mixtures in gasoline-powered internal combustion engines

The effects on combustion derived by the blending of hydrogen with traditional fuels adopted for internal combustion engines have been studied. Results derived by emission tests of a gasoline-fed vehicle equipped with a system for the production of hydrogen on-board have been analysed. The energy balance for the engine was evaluated. It demonstrated the increase of fuel consumptions to perform electrolysis process on-board the vehicle. Afterwards, numerical simulations based on a detailed kinetic model have been performed to calculate pollutant emissions produced by methane and iso-octane (which represents gasoline) compared with a mixture composed of 10% mol/mol by hydrogen. Chemical species studied were residual hydrocarbons, nitrous oxides and carbon monoxide. Notable variations of pollutant has not been calculated for methane, wherease iso-octane showed a reduction of the aforementioned pollutants when hydrogen was introduced. In the end operating costs have been analysed. The use of stored hydrogen produced by methane steam reforming found a reduction by 7% of costs, compared to the production via electrolysis.