Experimental Study of Rate of Heat Release of Sprays in Supercritical Direct Injection Combustion System Using Sensor

Investigation and modelling the effect of injection pressure on heat release parameters and engine-out nitrogen oxides are the main aim of this study. A zero-dimensional and multi-zone cylinder model was developed for estimation of the effect of injection pressure rise on performance parameters of diesel engine. Double-Wiebe rate of heat release global model was used to describe fuel combustion. extended Zeldovich mechanism and partial equilibrium approach were used for modelling the formation of nitrogen oxides. Single cylinder, high pressure direct injection, electronically controlled, research engine bench was used for model calibration. 1000 and 1200 bars of fuel injection pressure were investigated while injection advance, injected fuel quantity and engine speed kept constant. The ignition delay of injected fuel reduced 0.4 crank angle with 1200 bars of injection pressure and similar effect observed in premixed combustion phase duration which reduced 0.2 crank angle. Rate of heat release of premixed combustion phase increased 1.75 % with 1200 bar injection pressure. Multi-zone cylinder model showed good agreement with experimental in-cylinder pressure data. Also it was seen that the NOx formation model greatly predicted the engine-out NOx emissions for both of the operation modes.

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Experimental study of multiple pilot injection strategy in an automotive direct injection diesel engine

MATEC Web of Conferences ◽

10.1051/matecconf/201823403007 ◽

2018 ◽

Vol 234 ◽

pp. 03007

Author(s):

Plamen Punov ◽

Tsvetomir Gechev ◽

Svetoslav Mihalkov ◽

Pierre Podevin ◽

Dalibor Barta

Keyword(s):

Experimental Study ◽

Diesel Engine ◽

Diesel Engines ◽

Direct Injection ◽

Combustion Process ◽

Injection Timing ◽

Pilot Injection ◽

Injection Strategy ◽

Direct Injection Diesel Engine ◽

Rate Of Heat Release

The pilot injection strategy is a widely used approach for reducing the noise of the combustion process in direct injection diesel engines. In the last generation of automotive diesel engines up to several pilot injections could occur to better control the rate of heat release (ROHR) in the cylinder as well as the pollutant formation. However, determination of the timing and duration for each pilot injection needs to be precisely optimised. In this paper an experimental study of the pilot injection strategy was conducted on a direct injection diesel engine. Single and double pilot injection strategy was studied. The engine rated power is 100 kW at 4000 rpm while the rated torque is 320 Nm at 2000 rpm. An engine operating point determined by the rotation speed of 1400 rpm and torque of 100 Nm was chosen. The pilot and pre-injection timing was widely varied in order to study the influence on the combustion process as well as on the fuel consumption.

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Simulation and experimental coupled research of rate of heat release in DI diesel engine for various injection strategies

Combustion Engines ◽

10.19206/ce-117279 ◽

2008 ◽

Vol 132 (1) ◽

pp. 17-24

Author(s):

Kazimierz LEJDA ◽

Paweł WOŚ

Keyword(s):

Diesel Engine ◽

Heat Release ◽

Direct Injection ◽

Injection System ◽

Common Rail Injection System ◽

Common Rail Injection ◽

Release Analysis ◽

Di Diesel Engine ◽

Rate Of Heat Release ◽

Injection Strategies

In the paper the rate of heat release analysis in direct injection diesel engine has been presented and discussed. The research has been carried out for two different injection strategies, i.e. for conventional single-phase injection and for triple-phase injection executed by a Common Rail injection system. The calculation methodology of heat release rate based on indicator diagram has been presented as well.

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Accurate prediction of the rate of heat release in a modern direct injection diesel engine

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/095440700221600805 ◽

2002 ◽

Vol 216 (8) ◽

pp. 663-675 ◽

Cited By ~ 26

Author(s):

P A Lakshminarayanan ◽

Y V Aghav ◽

A D Dani ◽

P S Mehta

Keyword(s):

Diesel Engine ◽

Heat Release ◽

Direct Injection ◽

Turbulent Energy ◽

Operating Conditions ◽

Combustion Model ◽

Injection Velocity ◽

Mixing Rate ◽

Di Diesel Engine ◽

Rate Of Heat Release

An accurate model for the heat release rate in a modern direct injection (DI) diesel engine is newly evolved from the known mixing controlled combustion model. The combustion rate could be precisely described by relating the mixing rate to the turbulent energy created at the exit of the nozzle as a function of the injection velocity and by considering the dissipation of energy in free air and along the wall. The complete absence of tuning constants distinguishes the model from the other zero-dimensional or pseudomultidimensional models, at the same time retaining the simplicity. Successful prediction of the history of heat release in engines widely varying in bores, rated speeds and types of aspirations, at all operating conditions, validated the model.

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Study of cycle-by-cycle variations of natural gas direct injection combustion using a rapid compression machine

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/095440703762702978 ◽

2003 ◽

Vol 217 (1) ◽

pp. 53-61 ◽

Cited By ~ 20

Author(s):

Z Huang ◽

S Shiga ◽

T Ueda ◽

H Nakamura ◽

T Ishima ◽

...

Keyword(s):

Natural Gas ◽

Heat Release ◽

Maximum Rate ◽

Direct Injection ◽

Pressure Rise ◽

Maximum Pressure ◽

Rapid Compression Machine ◽

Combustion Duration ◽

Rate Of Heat Release ◽

Rapid Compression

Cycle-by-cycle variations of natural gas direct injection (CNG DI) combustion were studied by using a rapid compression machine. Results show that CNG DI combustion can realize high combustion stability with less cycle-by-cycle variation in the maximum pressure rise, the maximum rate of pressure rise and the maximum rate of heat release at the given equivalence ratios. Mixture stratification and fast flame propagation with the aid of turbulence produced by the high speed fuel jet are considered to be responsible for these behaviours. Cycle-by-cycle variations in combustion durations and combustion products present higher magnitudes than those of maximum pressure rise and maximum rate of heat release. Cycle-by-cycle variations of CO and unburned CH4 show an interdependence with the variation of the late combustion duration, and the variation of NO x shows an interdependence with the variation of the rapid combustion duration. Cycle-by-cycle variations are found to be insensitive to the equivalence ratios in CNG DI combustion.

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