Potential of a Hydrogen Fueled Opposed-Piston Four Stroke (OP4S) Engine

Abstract

<div class="section abstract"><div class="htmlview paragraph">The aim of this study is to develop a pathway towards Hydrogen combustoin on an opposed-piston four stroke engine (OP4S) by using 1D simulation code from Gamma Technologies. By its configuration, the OP4S engine has significant thermal efficiency benefits versus conventional ICE. The benefit of the OP4S is reduced heat losses due to elimination of the cylinder head, which increase the brake thermal efficiency.</div><div class="htmlview paragraph">A hydrogen-fueled (H2) opposed-piston four stroke (OP4S) engine was modeled using GTPower to determine the potential on performance, thermal efficiency and emissions targets. The 1D model was first validated on E10 gasoline using experimental data and was used to explore changes to fuel type in NG and H2, fueling location (TPI and DI), fuel mixture strength (stoichiometric and lean), for an optimized plenum volume and turbocharger selection.</div><div class="htmlview paragraph">The impact of these changes on volumetric efficiency, rated power, brake thermal efficiency and finally emissions for naturally aspirated and boosted conditions was determined. The simulation study demonstrates an engine design strategy for H2 fueled OP4S to meet power target of 20kW, brake thermal efficiency target of 40% and US EPA-Class II emission regulations for non-road small SI engine. The results also found that with a boosted stoichiometric burn direct injection H2 strategy combined with the OP4S can meet all performance and emission targets.</div></div>