EXPERIMENTAL ANALYSIS OF A HYDROGEN/DIESEL DUAL FUEL TEST CASE VIA IR IMAGING

Energy transition strongly leads researcher to find alternative fuel such as hydrogen to internal combustion engines. An immediate and transient solution is represented by the dual fuel (DF) technology. It can offer significant reduction of carbon dioxide and pollutant emissions. In this paper, DF operation was investigated in a single cylinder research engine. The engine run at 1500 rpm, while methane/hydrogen was injected in the intake manifold in front of the entrance of the tumble intake port. The aim of the study is to compare the DF hydrogen combustion with the DF methane combustion using Fast IR Imaging. We observed that IR camera was able to give combustion information and to follow the whole process for both DF hydrogen and methane, while identifying the combustion start point. Moreover, IR acquisitions for premixed hydrogen evidenced an unpredictably behavior of the mixture, leading to a specific Diesel injection strategy to avoid hydrogen auto-ignition at higher speed engine. Finally, premixed methane IR emission fully covered the combustion process, thus requiring a further image processing to get more information about the pilot and main injections.