Fuel-reforming effects on a gasoline direct injection engine under a low-temperature combustion mode: Experimental and kinetics analyses

Dedicated in-cylinder reforming where gasoline fuel is injected directly into a rich mixture can control the combustion of engines. This work investigates effects injection parameters and on direction (GDI) engine operated under low-temperature mode. The single-cylinder research modified from dedicated 4-cylinder spark-ignited used in subcompact passenger vehicles. Experimental kinetics results direct an oxygen-depleted environment engine’s recompression interval are analyzed 0.53 MPa indicated mean effective pressure 1500 RPM. Zero-dimensional simulations show that reactions net endothermic near-stoichiometric environments. Substantial short-chain hydrocarbons (CH4, C2H4, C3H6) reformed, while CO H2 small O2-depleted environment. These reformates strongly depend start timing (SOI). Consequently, species shorten predicted ignition delays play significant role advanced phasing. Validated 3D-CFD further indicate these combustion. Experimentally, SOI, Pinj = 5 6 MPa, single/double pulses injection, equivalence ratios ϕ varied intake strokes. Underϕ 0.97, excessive ringing intensities (RI) over MW/m2 observed SOIs. fierce combustion, noise metrics, NOx emissions be reduced significantly by retarding double-pulse variations. Under < 0.67, measured below 10 ppm. For all pulse-injection strategies, peak pressures dropped up to 13% lower than 2.0 motoring pressure, indicating occur during recompression. Therefore, reformed products chemically main 41 % thermal efficiency achievable.