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.

scholarly journals Modelling and Simulation of the Performance and Combustion Characteristics of a Locomotive Diesel Engine Operating on a Diesel–LNG Mixture

Energies ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5318
Author(s):  
Imantas Lipskis ◽  
Saugirdas Pukalskas ◽  
Paweł Droździel ◽  
Dalibor Barta ◽  
Vidas Žuraulis ◽  
...  
Keyword(s):  
Engine Performance ◽  
Fuel Mixture ◽  
Combustion Characteristics ◽  
Cylinder Pressure ◽  
Diesel Locomotive ◽  
Compression Ignition Engine ◽  
Locomotive Engine ◽  
Rate Of Heat Release ◽  
Fuel Mixtures ◽  
Locomotive Diesel

The article describes a compression-ignition engine working with a dual-fuel system installed in diesel locomotive TEP70 BS. The model of the locomotive engine has been created applying AVL BOOST and Diesel RK software and engine performance simulations. Combustion characteristics have been identified employing the mixtures of different fuels. The paper compares ecological (CO2, NOx, PM) and energy (in-cylinder pressure, temperature and the rate of heat release (ROHR)) indicators of a diesel and fuel mixtures-driven locomotive. The performed simulation has shown that different fuel proportions increased methane content and decreased diesel content in the fuel mixture, as well as causing higher in-cylinder pressure and ROHR; however, in-cylinder temperature dropped. CO2, NOx and PM emissions decrease in all cases thus raising methane and reducing diesel content in the fuel mixture.

Investigation of fuel properties and engine analysis of Jatropha biodiesel of Kenyan origin

2014 ◽  
Vol 25 (2) ◽  
pp. 107-116 ◽  
Author(s):  
Paul Maina
Keyword(s):  
Jatropha Curcas ◽  
Direct Injection ◽  
Data Acquisition System ◽  
Compression Ignition ◽  
Cylinder Pressure ◽  
Acid Base ◽  
Compression Ignition Engine ◽  
Crank Angle ◽  
Test Engine ◽  
Rate Of Heat Release

Biodiesel was produced from jatropha curcas oil of Kenyan origin through a two-step acid-base catalytic transesterification process. The relevant physicochemical properties of the produced biodiesel were tested according to appropriate standards and were found to be within the requirements. Engine tests were carried out in an Audi, 1.9 litre, turbocharged direct injection, compression ignition engine at different loads. Emissions were measured by a Horiba emission analyser system while combustion data was collected by a data acquisition system, from which, cylinder pressure and rate of heat release of the test engine in every crank angle were calculated. Though the biodiesel had slightly higher brake specific fuel consumption when compared to fossil diesel, its emission behaviour was significantly better. The combustion characteristics were also slightly higher as compared to fossil diesel. This study therefore concluded that biodiesel derived from jatropha curcas of Kenyan origin can be utilized as a safe substitute for mineral diesel.

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.

Analysis of Incylinder Pressure and Temperature Variation in a Four-Stroke S. I. Engine Using Wiebe’s Combustion Model

2014 ◽  
Vol 984-985 ◽  
pp. 957-961
Author(s):  
Vijayashree ◽  
P. Tamil Porai ◽  
N.V. Mahalakshmi ◽  
V. Ganesan
Keyword(s):  
Heat Release ◽  
Combustion Process ◽  
Pressure Variation ◽  
Spark Ignition Engine ◽  
Working Fluid ◽  
Combustion Model ◽  
Cylinder Pressure ◽  
Crank Angle ◽  
Experimental Values ◽  
Release Model

This paper presents the modeling of in-cylinder pressure variation of a four-stroke single cylinder spark ignition engine. It uses instantaneous properties of working fluid, viz., gasoline to calculate heat release rates, needed to quantify combustion development. Cylinder pressure variation with respect to either volume or crank angle gives valuable information about the combustion process. The analysis of the pressure – volume or pressure-theta data of a engine cycle is a classical tool for engine studies. This paper aims at demonstrating the modeling of pressure variation as a function of crank angle as well as volume with the help of MATLAB program developed for this purpose. Towards this end, Woschni heat release model is used for the combustion process. The important parameter, viz., peak pressure for different compression ratios are used in the analysis. Predicted results are compared with experimental values obtained for a typical compression ratio of 8.3.

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.

Study on the Combustion Characteristics of the Engine Fueled with DME-Diesel Blends

2014 ◽  
Vol 953-954 ◽  
pp. 1381-1385
Author(s):  
Wei Li ◽  
Yun Peng Li ◽  
Fan Bin Li
Keyword(s):  
Heat Release ◽  
Pressure Rise ◽  
Mechanical Efficiency ◽  
Diesel Oil ◽  
Cylinder Pressure ◽  
Mass Ratio ◽  
Combustion Duration ◽  
Crank Angle ◽  
Maximum Combustion Temperature ◽  
Stroke Engine

To further study the performance of the engine fueled with DME-diesel blends, the indicator diagrams of a two-cylinder four-stroke engine are recorded at 1700r/min and 2300r/min under different load, the heat release rate and the rate of pressure rise are calculated. The results show that: when fueled the engine with D20 blend (Mass ratio of DME and diesel oil is 2:10) and optimizing the fuel supply advance angle, the maximum cylinder pressure decreases by 10% averagely and its corresponding crank angle delays 2°CA, the maximum rate of pressure rise is relatively lowers about 20%, the beginning of heat release delays，but combustion duration do not extend, and the centroid of heat release curves is closer to TDC (Top Dead Center), maximum combustion temperature drops 70-90K. These results indicate that the mechanical efficiency will be improved and, NOx emissions and mechanical noise will be reduced when an engine fueled with DME-diesel blends.

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.

Effect of Mahua Biodiesel Blends on the Combustion Characteristics of Direct Injection CI Engine at Various Compression Ratios

2015 ◽  
Vol 813-814 ◽  
pp. 824-829
Author(s):  
Ramani Vagesh Shangar ◽  
Venkatesan Hariram
Keyword(s):  
Heat Release ◽  
Compression Ratio ◽  
Ignition Delay ◽  
Direct Injection ◽  
Combustion Characteristics ◽  
Cylinder Pressure ◽  
Biodiesel Blends ◽  
Peak Cylinder Pressure ◽  
Ci Engine ◽  
Mahua Biodiesel

In the current study, combustion characteristics were evaluated using mahua biodiesel blends at different compression ratios on a direct injection CI engine. Non edible mahua oil was transesterified into biodiesel by two stage technique. Combustion parameters were evaluated for B5, B10 and B20 blends of mahua biodiesel with diesel and they were compared with straight diesel at compression ratios of 16, 17 and 18.Compression ratio was varied without altering the combustion chamber geometry and the static spill timing was set to 23° bTDC. Parameters like In cylinder pressure, heat release rate, rate of pressure rise and cumulative heat release were evaluated in this study at 100% engine loading conditions. Higher peak cylinder pressure and heat release was observed at higher compression ratios. The ignition delay of the blends were slightly higher compared to diesel at all CR tested. Peak cylinder pressure of the blends was slightly higher at CR 18. The ignition delay was also observed to be lower at higher compression ratio. The peak pressure was observed closer to TDC at higher compression ratios for all fuels tested.

Research on Combustion Characteristics and Emissions of Methanol-Diesel Fuel with Different Additives

2011 ◽  
Vol 354-355 ◽  
pp. 462-467
Author(s):  
Cui Ping Zhang ◽  
Xu Mao Zhai ◽  
Yu Juan Li ◽  
Zhi Gang Sun
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Dimethyl Ether ◽  
Diesel Fuel ◽  
Release Rate ◽  
Combustion Characteristics ◽  
Soot Emission ◽  
Cylinder Pressure ◽  
Initial Stage ◽  
Co Emission

Methanol and diesel are almost not soluble, which greatly limits the further study and popularization of the methanol-diesel fuel. To study the emission and combustion characteristics, the 4100 turbocharged and intercooled diesel engine was fueled with 0# diesel and M10 with different additives in the experiment. The result shows that, the maximum cylinder pressure and the peak of the heat release rate in the initial stage of combustion for M10 with iso-octanol and isooctyl nitrate as additive are higher than that of diesel, while the soot emission is lower and NOx emission is slightly higher than diesel’. The maximum cylinder pressure and the heat-release peak in the initial stage of combustion for M10 with dimethyl ether as additive are both lower than diesel’, and the NOx and soot emissions are obviously decreased. The power of the two blend fuels is lower than that of diesel but the magnitude is small, meanwhile the HC emission is slightly increased, while the CO emission is little declined.

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.

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