Combustion in Gas‐fueled Compression Ignition Engines of the Dual Fuel Type

Abstract

In the dual fuel engine, much of the energy release comes from the combustion of the gaseous fuel and only a small amount of diesel liquid fuel provides ignition through timed cylinder injection. Such operation with optimum conversion methods has the potential to provide operational characteristics that are comparable or superior to those of the corresponding diesel or spark ignition engines. These characteristics may be realized only if sufficiently effective measures can be ensured both for the avoidance of knock, usually at high loads, and incomplete gaseous fuel utilization at relatively light loads. To overcome these problems associated with the operation of dual fuel engines over a wide range of fuels and their mixtures, better control of the relatively complex processes of combustion is essential. Both experimental and analytical modeling procedures for effecting optimum improvements to the combustion process are described.

Investigations on the combustion duration and ignition delay period of a dual fuel diesel engine with hydrogen and producer gas as secondary fuels

“…Also, changes in the intake partial pressure of oxygen due to air displacement by the gaseous fuel, changes in the pre-ignition reaction activity and its associated heat release and the effect of residual gas can bring about substantial changes to the pre-ignition processes of the pilot and hence the length of the delay period [13,14].…”

Biodiesel, emulsified biodiesel and dimethyl ether as pilot fuels for natural gas fuelled engines

“…Dual-fuelling in CI engines would allow the reduction of smoke and NO x emissions common in conventional CI engine exhaust while maintaining the characteristically high CI engine thermal efficiencies. Different main (high-octane) fuels have been used, with natural gas and hydrogen gas in particular having been researched extensively [24][25][26][27][28][29][30][31][32][33][34][35]. These fuels were selected for their high octane number compared to gasoline (around 120 RON and 95 RON respectively).…”

Theoretical study of the effects of engine parameters on performance and emissions of a pilot ignited natural gas diesel engine☆

“…In PINGD engine the air supply is not throttled while q Presented at the ECOS 2008 Conference. the engine power output is controlled by changing the amount of the primary gaseous fuel (i.e., natural gas) [5,6]. Moreover, when engine operates at constant engine speed, the change in the amount of the gaseous fuel results in a change in the amount of the inducted combustion air since the total amount of the inducted mixture (i.e., gaseous fuel and air) is kept constant.…”

“…Moreover, when engine operates at constant engine speed, the change in the amount of the gaseous fuel results in a change in the amount of the inducted combustion air since the total amount of the inducted mixture (i.e., gaseous fuel and air) is kept constant. Most current dual fuel engines are made to operate either on dual fuel principle with diesel ignition, or simply as conventional diesel engines [5,6].…”

“…Many research studies [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] have reported that, the main drawback of pilot ignited natural gas/diesel engine operation in contrast with conventional diesel operation, is the negative effect on engine efficiency, carbon monoxide (CO) and unburned hydrocarbon (HC) emissions, especially at low and intermediate load operating points. At high load, the improvement of gaseous fuel utilization leads to a relevant improvement of both engine performance and carbon monoxide emissions, but their values continue to be inferior to the respective values observed under normal diesel operation.…”