Effect of Gliding Arc Plasma Reforming of Methane on Large-Bore Low-Speed Two-Stroke Marine Engine

As a clean fuel from a wide range of sources, natural gas can effectively improve the emission performance of large-bore low-speed marine engines. The high ignition energy and low flame propagation speed of natural gas can be effectively solved by using hydrogen or syngas from fuel reforming. In this study, a gliding arc plasma reforming reactor was utilized to reform methane, the main component of natural gas. Reforming was studied for different O/C molar ratios and input power. Based on the obtained ratios of reforming product components (H2 and CO, etc.), numerical simulation was used to study the combustion and emission characteristics of the engine under different fuel reforming ratios. The reforming gas enters the engine through the natural gas intake valve. The results show that the products of gliding arc plasma reforming can effectively enhance the flame propagation in the cylinder, forward the center of exothermic heat release, and shorten the combustion duration. Meanwhile, it can reduce emissions of unburned natural gas.