Rate of Heat Release Prediction for Direct Injection Diesel Engines Based on Purely Mixing Controlled Combustion

Author(s):  
Franz G. Chmela ◽  
Gerhard C. Orthaber
Author(s):  
Peter G. Dowell ◽  
Sam Akehurst ◽  
Richard D. Burke

To meet the increasingly stringent emissions standards, diesel engines need to include more active technologies with their associated control systems. Hardware-in-the-loop (HiL) approaches are becoming popular where the engine system is represented as a real-time capable model to allow development of the controller hardware and software without the need for the real engine system. This paper focusses on the engine model required in such approaches. A number of semi-physical, zero-dimensional combustion modeling techniques are enhanced and combined into a complete model, these include—ignition delay, premixed and diffusion combustion and wall impingement. In addition, a fuel injection model was used to provide fuel injection rate from solenoid energizing signals. The model was parameterized using a small set of experimental data from an engine dynamometer test facility and validated against a complete data set covering the full engine speed and torque range. The model was shown to characterize the rate of heat release (RoHR) well over the engine speed and load range. Critically, the wall impingement model improved R2 value for maximum RoHR from 0.89 to 0.96. This was reflected in the model's ability to match both pilot and main combustion phasing, and peak heat release rates derived from measured data. The model predicted indicated mean effective pressure and maximum pressure with R2 values of 0.99 across the engine map. The worst prediction was for the angle of maximum pressure which had an R2 of 0.74. The results demonstrate the predictive ability of the model, with only a small set of empirical data for training—this is a key advantage over conventional methods. The fuel injection model yielded good results for predicted injection quantity (R2 = 0.99) and enabled the use of the RoHR model without the need for measured rate of injection.


2014 ◽  
Vol 18 (1) ◽  
pp. 155-168 ◽  
Author(s):  
Levent Yüksek ◽  
Tarkan Sandalci ◽  
Orkun Özener ◽  
Alp Ergenc

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.


2018 ◽  
Vol 234 ◽  
pp. 03007
Author(s):  
Plamen Punov ◽  
Tsvetomir Gechev ◽  
Svetoslav Mihalkov ◽  
Pierre Podevin ◽  
Dalibor Barta

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.


Author(s):  
Marcelo A. Pasqualette ◽  
Diego C. Estumano ◽  
Fabiana C. Hamilton ◽  
Marcelo J. Colaço ◽  
Albino J. K. Leiroz ◽  
...  

2018 ◽  
Vol 11 (21) ◽  
pp. 1-8
Author(s):  
Jorge Duarte Forero ◽  
Guillermo E. Valencia ◽  
Luis G. Obregon ◽  
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◽  
...  

Author(s):  
H. C. Grigg ◽  
M. H. Syed

Two simple models for the rate of heat release in diesel engines are described. The factors taken into account in the models are rate of entrainment of air into the fuel sprays, the rate of turbulent mixing of fuel and air within the spray, and the chemical kinetics of burning. The models differ in their treatment of the rate of air entrainment. Comparisons are made with experimental results for a diesel engine running at two speeds and a variety of turbocharging ratios. The overall agreement with experiment in respect of shape of rate of heat release diagram is good, with the exception of the naturally aspirated cases where the rate of air entrainment is too low.


2008 ◽  
Vol 132 (1) ◽  
pp. 17-24
Author(s):  
Kazimierz LEJDA ◽  
Paweł WOŚ

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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