Lean-burn characteristics of a turbocharged opposed rotary piston engine fuelled with hydrogen at low engine speed conditions

Opposed rotary piston (ORP) engines have high power density and compact designs which meet the requirements of sources hybrid vehicles. Hydrogen applications to ORP can effectively decrease greenhouse gas emissions; however, hydrogen combustion in around stoichiometric ratio generated large quantities nitrogen oxides (NOx), especially for low engine speed conditions. Lean-burn as an effective method NOx emissions was adopted this research. A 3D numerical simulation used explore effect equivalence (≤1) on emission characteristics fuelled with hydrogen. The results indicated that peak in-cylinder pressure increased 1000 revolutions per minute (RPM); value over 0.9 maximum among 2000 RPM scenarios. heat release rates greatly dependent speeds. Start advanced increase ratio; it earliest at During exhaust stroke, free discharge much higher than atmosphere pressure, significantly pumping losses stroke. Accumulated reached given speeds; were almost zero severe lean-burn (<0.7) Engine output decreased drop thermal efficiency speed.