The effect of injection parameters and boost pressure on diesel-propane dual fuel low temperature combustion in a single-cylinder research engine

Abstract

Diesel-ignited propane dual fuel low temperature combustion was characterized in a singlecylinder research engine (SCRE) at constant values of indicated mean effective pressure (IMEP of 5.1 bar), engine speed (1500 rpm), and propane energy substitution (PES = 80%). The effects of three important engine parameters (start of injection (SOI) of diesel fuel, common-rail pressure (Prail) for diesel injection, and boost pressure (Pin)) on engine performance, combustion, and emissions were examined. As SOI was advanced from 355 absolute crank angle degrees (CAD) (or 5° BTDC) to 280 CAD for constant Prail = 500 bar and Pin = 1.5 bar, the apparent heat release rate (AHRR) profiles changed from a two-stage, "diesel-like" combustion process to a smooth, "Gaussian-like," single-stage combustion process, that was representative of more homogeneous combustion. In addition, with SOI advancement, the combustion phasing (CA50) was initially advanced but eventually occurred later for very early SOIs. Indicated-specific emissions of oxides of nitrogen (ISNOx) were reduced to about 0.12 g/kWh for SOIs advanced beyond 310 CAD while maintaining high indicated fuel conversion efficiencies (IFCEs). While smoke emissions were below 0.1 FSN for all conditions tested in this study, indicated-specific hydrocarbon (ISHC) and

Impact of methane energy fraction on emissions, performance and cyclic variability in low-load dual fuel combustion at early injection timings

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“…High UHC and CO emissions, particularly at low engine loads, are attributed to natural gas trapped in crevices and to lower reactivity of natural gas leading to flame quench. 21,22,27–29…”

Separate and combined effects of hydrogen and nitrogen additions on diesel engine combustion

“…Shortage of non-renewable energies and increase in fuel prices such as diesel and gasoline causes the development of a new study field which deals with the investigation the effects of biofuels and fuel additives on the diesel engines parameters. Many researchers have studied the effects of various fuels and fuel additives such as natural gas [13][14], syngas [15], Iso-Butanol [16][17], propane [18] and hydrogen gas [19][20] on engine performance and amounts of output emissions. In their study, Chun et al have investigated the influence of H2 gas addition on the emissions formation and performance of a diesel engine [21].…”

Numerical Investigation on Effects of Assigned EGR Stratification on a Heavy Duty Diesel Engine with Two-Stage Fuel Injection

“…Therefore, in recent years, high exhaust gas recirculation (EGR) and flexible two-stage fuel injection [4][5][6][7][8][9] are becoming increasingly popular due to their capability to control combustion temperature and fuel/oxygen ratio. Homogeneous charge compression ignition (HCCI) combustion [10,11], low temperature combustion [12] and high dilution combustion [13,14] are successful new combustion concepts for reducing engine-out toxic emissions by reducing oxygen and combustion temperature using high EGR, however, at the expense of high fuel consumption [15] and a narrow operation range in HCCI combustion [16]. Combustion efficiency also deteriorates [17] due to the high dilution effects of EGR.…”