Cylinder Pressure Information-Based Postinjection Timing Control for Aftertreatment System Regeneration in a Diesel Engine—Part I: Derivation of Control Parameter

2016 ◽  
Vol 138 (8) ◽  
Author(s):  
Hyunjun Lee ◽  
Manbae Han ◽  
Myoungho Sunwoo
Keyword(s):  
Phase Shift ◽  
Heat Release ◽  
Exhaust Emissions ◽  
Cylinder Pressure ◽  
Combustion Analysis ◽  
Operating Condition ◽  
Combustion Phase ◽  
Rate Of Heat Release ◽  
Engine Operating Condition ◽  
Aftertreatment Systems

The implementation of aftertreatment systems in passenger car diesel engines, such as a lean NOx trap (LNT) and a diesel particulate filter (DPF), requires an in-cylinder postinjection (POI) for a periodic regeneration of those aftertreatment systems to consistently reduce tail-pipe emissions. Although the combustion and emission characteristics are changed from the normal engine operating conditions due to the POI, POI is generally applied with a look-up table (LUT) based feedforward control because of its cost effectiveness and easy implementation into the engine management system (EMS). However, the LUT-based POI control necessities tremendous calibration work to find the optimal timing to supply high exhaust gas temperature or enough reductants such as carbon monoxide (CO) and hydrocarbon to regenerate the aftertreatment systems while maintaining low engine-out smoke emissions. To solve this problem, we propose a novel combustion analysis method based on the cylinder pressure information. This method investigates the relation between the POI timing with the exhaust emissions and compensates the combustion phase shift occurred by the engine operating condition changes, such as the engine speed and injection quantity. A burning rate of fuel after a location of the rate of heat release maximum (BRaLoROHRmax) was derived from the combustion analysis. A mass fraction burned X% after a location of the rate of heat release maximum (MFBXaLoROHRmax) was determined using the BRaLoROHRmax and main injection (MI) quantity. Nonlinear characteristics of the exhaust emissions according to POI timing variations and the combustion phase shift due to the engine operating condition changes can be easily analyzed and compensated in terms of the proposed MFBXaLoROHRmax domain. The proposed method successfully evaluated its utility through the engine experiments for the LNT and DPF regeneration.

scholarly journals Modelling the effect of injection pressure on heat release parameters and nitrogen oxides in direct injection diesel engines

2014 ◽  
Vol 18 (1) ◽  
pp. 155-168 ◽  
Author(s):  
Levent Yüksek ◽  
Tarkan Sandalci ◽  
Orkun Özener ◽  
Alp Ergenc
Keyword(s):  
Nitrogen Oxides ◽  
Heat Release ◽  
Direct Injection ◽  
Pressure Rise ◽  
Injection Pressure ◽  
Premixed Combustion ◽  
Crank Angle ◽  
Cylinder Model ◽  
Combustion Phase ◽  
Rate Of Heat Release

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.

Influence of piston bowl geometry on combustion and emission characteristics

2019 ◽  
Vol 233 (5) ◽  
pp. 576-587 ◽  
Author(s):  
Ramazan Şener ◽  
Mehmed R Özdemir ◽  
Murat U Yangaz
Keyword(s):  
Heat Release ◽  
Renewable Energy Sources ◽  
Combustion Characteristics ◽  
Emission Rates ◽  
Cylinder Pressure ◽  
Compression Ignition Engine ◽  
Piston Bowl ◽  
Crank Angle ◽  
Rate Of Heat Release ◽  
Exhaust Valves

Together with the global energy concerns, the norms are getting stringent to prevent the emission threat. There are on-going studies on systems working with both fossil and renewable energy sources aiming to create more efficient and less emissive processes and devices. Accordingly, a set of numerical simulations was performed to examine the effect of the bowl shape of a piston on the performance behaviour, emission rates and combustion characteristics in a four-cylinder, four strokes, water-cooled compression ignition engine using n-heptane (C7H16) as fuel. Six different piston bowl geometries, five from the literature and proposed one, were utilized having different length-to-diameter ratio, curvature and sidewall radius. The study was conducted at 1750 r/min engine speed and a constant compression ratio with a full performance condition. The intake and exhaust valves have been considered as closed during the analysis to provide the variation of crank angle from 300 CA to 495 CA. The results showed that the piston bowl geometry has a significant impact on the rate of heat release, in-cylinder pressure, in-cylinder temperature, and emission trends in the engine. Among the piston bowl geometries studied, design DE and design DF exhibited better combustion characteristics and relatively lower emission trends compared to other designs. The observed rate of heat release, in-cylinder pressure and in-cylinder temperature magnitudes of these two geometries was higher in comparison to other geometries. Moreover, the trade-off for NOx emission was also observed higher for these piston bowl designs.

Effect of Cryogenic Intake Air Temperature on the In-Cylinder Temperature and Formation of Exhaust Emissions in a Compression Ignition Engine

2019 ◽  
Vol 141 (9) ◽  
Author(s):  
Se Hun Min ◽  
Hyun Kyu Suh ◽  
Seongin Jo ◽  
Suhan Park
Keyword(s):  
Air Temperature ◽  
Mass Fraction ◽  
Equivalence Ratio ◽  
Exhaust Emissions ◽  
Compression Ignition ◽  
Cylinder Pressure ◽  
Compression Ignition Engine ◽  
Rate Of Heat Release ◽  
Ci Engine ◽  
Combustion Behaviors

The objective of this study is to numerically investigate the effect of cryogenic intake air temperature on the in-cylinder temperature and formation of exhaust emissions in a CI engine. The experimental setup was consisted of a single-cylinder diesel engine. The intake air temperature was varied from 18 °C to 40 °C, which was controlled by cooler and heater. Submodels were applied for the simulations of physical/chemical phenomenon of spray and combustion behaviors. The intake air temperature in numerical condition was varied from −18 °C to 18 °C. The numerical results were validated with experimental results for the reliability of this work. The results of this work were compared in terms of cylinder pressure, rate of heat release (ROHR), indicated specific nitrogen oxide (ISNO), indicated specific carbon monoxide (ISCO), ignition delay, in-cylinder temperature distributions, equivalence ratio distributions, NO mass fraction, and CO mass fraction. When the intake air temperature was decreased in steps of 9 °C, the cylinder temperature and cylinder pressure were decreased in steps of about 14.5 °C and 0.05 MPa, respectively. In all cases, the area where the NO formed in the cylinder was identified with the area of the high equivalence ratio and temperature in the cylinder. The amount of CO generation shows the similar distributions in the cylinder according to the intake air temperature conditions. However, the oxidation rate of formed CO under the low intake air temperature was lower than those of the high intake air temperature.

Evaluating the combustion and emission phenomenon of algal and cotton seed biodiesel as fuel for compression ignition engine

2019 ◽  
Vol 16 (2) ◽  
pp. 222-231 ◽  
Author(s):  
Hariram Venkatesan ◽  
Godwin John J. ◽  
Seralathan Sivamani
Keyword(s):  
Heat Release ◽  
Pressure Rise ◽  
Emission Characteristics ◽  
Compression Ignition ◽  
Cylinder Pressure ◽  
Compression Ignition Engine ◽  
Content Type ◽  
Algal Oil ◽  
Algal Biodiesel ◽  
Rate Of Heat Release

Purpose Vast areas have been studied toward combustion and emission analysis in vegetable oil methyl esters and quite a few in algal oil biodiesel. To analyze the better alternate source for diesel engine, this study aims to investigate the combustion behavior and emission characteristics between cottonseed biodiesel and algal oil biodiesel on comparison with mineral diesel in a compression ignition engine. Design/methodology/approach The fuel properties like density, kinematic viscosity, calorific value and Cetane number have met the biodiesel standards for both algal and cottonseed biodiesel. At rated power, engine was operated on all three test fuels, where combustion analysis describing in-cylinder pressure, peak pressure, rate of pressure rise and rate of heat release and emission characteristics including hydrocarbon (HC), carbon monoxide (CO), oxides of nitrogen (NOx) and smoke for both biodiesel comparing mineral diesel. Findings Algal and cottonseed biodiesel showed up to 2-3°CA delayed start of combustion comparing mineral diesel curve. The in-cylinder pressure of algal biodiesel was found to be 68 bar, whereas cottonseed biodiesel exhibited 65 bar at full load condition. Similarly, the rate of pressure rise and rate of heat release of algal biodiesel depicted 7.9 and 10.7 per cent rise than cottonseed biodiesel, respectively. As the load increased, ignition delay showed decreasing trend, while combustion duration showed an increasing trend. HC, CO and smoke emissions were seen to be lower than mineral diesel with noticeable increase in NOx emission. Originality/value In this present investigation, biodiesel from Stoechospermum Marginatum, a marine marco algae, was used to fuel the compression ignition engine. Its combustion behavior and emission characteristics are compared with cottonseed biodiesel, a vegetable oil-based biodiesel having similar physio-chemical characteristics to understand the suitability of algal biodiesel in compression ignition engine. This study involves the assessment of straight biodiesel from macro algae and cottonseed oil on standard operating conditions.

scholarly journals The Study on the Effect of the Piston Shapes through Biodiesel Mixture Combustion in Diesel Engine

2018 ◽  
Vol 53 ◽  
pp. 03022
Author(s):  
Changchun Xu ◽  
Md. Abul Kalam ◽  
HaengMuk Cho
Keyword(s):  
Heat Release ◽  
Direct Injection ◽  
Exhaust Emissions ◽  
Injection Rate ◽  
Combustion Characteristics ◽  
Main Peak ◽  
Flat Bottom ◽  
Flow Energy ◽  
Low Viscosity ◽  
Combustion Phase

In this work, we studied the combustion characteristics of a direct injection compression ignition (DICI) engine. Diesel uses different cylinder geometry and different injection rate shapes. We can change the piston surface to compare turbulent flow energy and eddy viscosity. So we use three geometric piston bowls for comparison. The geometry is set to a single circle, a double circle and a flat bottom so that the engine combustion characteristics can be improved and the exhaust emissions can be reduced. Therefore, we can find through simulation that a double circular geometry piston with a better geometry has the highest turbulent kinetic energy (TKE) and this results in two peak heat releases with a main peak heat release during premixed combustion. And secondary peak heat release occurs during the mixed controlled combustion phase. This article adopts this geometry. The air-biofuel mixture can be squeezed in two wheels because better vortexing can squeeze the mixture better to improve the mixture. Therefore, this article will examine the bowl-shaped geometries that produce high-KTE and low-viscosity fuels, single-circle geometries, double-circular geometries, and flat base geometries. In general, we can increase the air/fuel ratio by changing the geometry to reduce exhaust emissions.

Rate of Heat Release in Diesel Engines and Its Correlation with Fuel Injection Data

1969 ◽  
Vol 184 (10) ◽  
pp. 17-27 ◽  
Author(s):  
N. D. Whitehouse ◽  
R. Way
Keyword(s):  
Heat Release ◽  
Diesel Engines ◽  
Simple Formula ◽  
Fuel Injection ◽  
Medium Size ◽  
Zone Model ◽  
Cylinder Pressure ◽  
Air Supply ◽  
Rate Of Heat Release ◽  
Release Data

Basic heat release data have been obtained by analysis of cylinder pressure diagrams from a variety of engines, two-stroke and four-stroke, small (3·4-in bore) to medium size (12-in bore) over ranges of power, speed, and air supply conditions. The paper gives an account of early attempts to obtain a simple formula for heat release suitable for performance calculations by computer, using the simple and widely used single-zone model for conditions in the cylinder. The conclusion is reached that although it is possible to obtain useful calculations in this way, more sophisticated models are necessary for better understanding of conditions in the engine.

scholarly journals Engine Malfunctioning Conditions Identification through Instantaneous Crankshaft Torque Measurement Analysis

2021 ◽  
Vol 11 (8) ◽  
pp. 3522
Author(s):  
Konstantinos-Marios Tsitsilonis ◽  
Gerasimos Theotokatos
Keyword(s):  
Operating Conditions ◽  
Cylinder Pressure ◽  
Dynamics Model ◽  
Engine Model ◽  
Measurement Analysis ◽  
Start Of Injection ◽  
Rate Of Heat Release ◽  
Relationship Of ◽  
Diagnostic Measurement ◽  
The Relationship

In this study a coupled thermodynamics and crankshaft dynamics model of a large two-stroke diesel engine was utilised, to map the relationship of the engine Instantaneous Crankshaft Torque (ICT) with the following frequently occurring malfunctioning conditions: (a) change in Start of Injection (SOI), (b) change in Rate of Heat Release (RHR), (c) change in scavenge air pressure, and (d) blowby. This was performed using frequency analysis on the engine ICT, which was obtained through a series of parametric runs of the coupled engine model, under the various malfunctioning and healthy operating conditions. This process demonstrated that engine ICT can be successfully utilised to identify the distinct effects of malfunctions (c) or (d), as they occur individually in any cylinder. Furthermore by using the same process, malfunctions (a) and (b) can be identified as they occur individually for any cylinder, however there is no distinct effect on the engine ICT among these malfunctions, since their effect on the in-cylinder pressure is similar. As a result, this study demonstrates the usefulness of the engine ICT as a non-intrusive diagnostic measurement, as well as the benefits of malfunctioning conditions mapping, which allows for quick and less resource intensive identification of engine malfunctions.

scholarly journals Experimental and Simulation of Diesel Engine Fueled with Biodiesel with Variations in Heat Loss Model

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1622
Author(s):  
Daniel Romeo Kamta Legue ◽  
Zacharie Merlin Ayissi ◽  
Mahamat Hassane Babikir ◽  
Marcel Obounou ◽  
Henri Paul Ekobena Fouda
Keyword(s):  
Heat Release ◽  
Heat Loss ◽  
Heat Release Rate ◽  
Release Rate ◽  
Diffusion Combustion ◽  
Cylinder Wall ◽  
Compression Ignition Engine ◽  
Experimental Conditions ◽  
Load Range ◽  
Combustion Phase

This study presents an experimental investigation and thermodynamic 0D modeling of the combustion of a compression-ignition engine, fueled by an alternative fuel based on neem biodiesel (B100) as well as conventional diesel (D100). The study highlights the effects of the engine load at 50%, 75% and 100% and the influence of the heat loss models proposed by Woschni, Eichelberg and Hohenberg on the variation in the cylinder pressure. The study shows that the heat loss through the cylinder wall is more pronounced during diffusion combustion regardless of the nature of the fuels tested and the load range required. The cylinder pressures when using B100 estimated at 89 bars are relatively higher than when using D100, about 3.3% greater under the same experimental conditions. It is also observed that the problem of the high pressure associated with the use of biodiesels in engines can be solved by optimizing the ignition delay. The net heat release rate remains roughly the same when using D100 and B100 at 100% load. At low loads, the D100 heat release rate is higher than B100. The investigation shows how wall heat losses are more pronounced in the diffusion combustion phase, relative to the premix phase, by presenting variations in the curves.

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