scholarly journals EXPERIMENTAL INVESTIGATIONS OF HYDROGEN EFFECTS ON PERFORMANCE AND EMISSIONS OF RENEWABLE DIESEL FUELED RCCI / VANDENILIO ĮTAKA ENERGINIAMS IR EMISIJOS RODIKLIAMS ALTERNATYVIU DYZELINU VEIKIANČIAME RCCI VARIKLYJE – EKSPERIMENTINIS TYRIMAS

2018 ◽  
Vol 10 (0) ◽  
pp. 1-10
Author(s):  
Romualdas Juknelevičius
Keyword(s):  
Combustion Chamber ◽  
Combustion Process ◽  
Engine Performance ◽  
Fuel Mixture ◽  
Injection System ◽  
Experimental Investigations ◽  
Renewable Diesel ◽  
Common Rail Injection System ◽  
Performance And Emissions ◽  
The Rich

The article presents the study of hydrogen effects on performance, combustion and emissions characteristics of renewable diesel fueled single cylinder CI engine with common rail injection system in RCCI mode. The renewable diesel fuels as the HRF are the HVO and it blend with petrol diesel further named PRO Diesel, investigated in this study. The purpose of this investigation was to examine the influence of the LRF – hydrogen addition to the HRF on combustion phases, engine performance, efficiency, and exhaust emissions. HES was changed within the range from 0 to 35%. Hydrogen injected through PFI during intake stroke to the combustion chamber, where it created homogeneous mixture with air. The HRF was directly injected into combustion chamber using electronic controlled unit. Tests were performed at both fixed and optimal injection timings at low, medium and nominal engine load. After analysis of the engine bench results, it was observed that lean hydrogen – HRF mixture does not support the flame propagation and efficient combustion. While at the rich fuel mixture and with increasing hydrogen fraction, the combustion intensity concentrate at the beginning of the combustion process and shortened the ignition delay phase. Decrease of CO, CO2 and smoke opacity was observed with increase of hydrogen amounts to the engine. However, increase of the NO concentration in the engine exhaust gases was observed.

scholarly journals RME CO-COMBUSTION WITH HYDROGEN IN COMPRESSION IGNITION ENGINE: PERFORMANCE, EFFICIENCY AND EMISSIONS / SLĖGINIO UŽDEGIMO VARIKLIO ENERGINIŲ, EFEKTYVUMO IR DEGINIŲ EMISIJOS RODIKLIŲ TYRIMAS NAUDOJANT RAPSŲ METILESTERĮ IR VANDENILĮ

2018 ◽  
Vol 10 (0) ◽  
pp. 1-9
Author(s):  
Romualdas Juknelevičius
Keyword(s):  
Combustion Process ◽  
Engine Performance ◽  
Fuel Mixture ◽  
Common Rail ◽  
Injection System ◽  
Intake Manifold ◽  
Compression Ignition Engine ◽  
Common Rail Injection System ◽  
Wide Range ◽  
The Rich

The article presents the test results of the single cylinder CI engine with common rail injection system operating on biofuel – Rapeseed Methyl Ester with addition supply of hydrogen. The purpose of this investigation was to examine the influence of the hydrogen addition to the biofuel on combustion phases, engine performance, efficiency, and exhaust emissions. HES was changed within the range from 0 to 44%. Hydrogen was injected into the intake manifold, where it created homogeneous mixture with air. Tests were performed at both fixed and optimal injection timings at low, medium and nominal engine load. After analysis of the engine bench tests and simulation with AVL BOOST software, it was observed that lean hydrogen – RME mixture does not support the flame propagation and efficient combustion. While at the rich fuel mixture and with increasing hydrogen fraction, the combustion intensity concentrate at the beginning of the combustion process and shortened the ignition delay phase. AVL BOOST simulation performed within the wide range of HES (16–80%) revealed that combustion intensity moves to the beginning of combustion with increase of HES. Decrease of CO, CO2 and smoke opacity was observed with increase of hydrogen amounts to the engine. However, increase of the NO concentration in the engine exhaust gases was observed. Santrauka Straipsnyje pateikti tyrimo rezultatai, gauti atlikus bandymą vieno cilindro slėginio uždegimo variklyje su biodegalais – rapsų metilesterį (RME) ir vandenilį. Biodegalai įpurškiami akumuliatorine įpurškimo sistema „Common rail“. Šio tyrimo tikslas – ištirti, kaip vandenilis veikia biodegalų degimą, variklio veikimą, jo efektyvumą ir deginių susidarymą. Vandenilio energinė dalis degimo mišinyje buvo keičiama nuo 0 iki 44 %. Vandenilis buvo tiekiamas įsiurbimo fazės metu įsiurbimo kanalu į degimo kamerą, kurioje jis, susimaišęs su oru, sudaro homogeninį mišinį. Bandymai buvo atliekami nekeičiant įpurškimo kampo, nustačius optimalų įpurškimo kampą esant žemai, vidutinei ir nominaliai variklio apkrovai. Išnagrinėjus variklio bandymų rezultatus ir sumodeliavu AVL BOOST programa, buvo pastebėta, kad, esant liesam vandenilio ir RME mišiniui, liepsnos plitimas yra lėtas, mišinys dega neveiksmingai. Tačiau riebus degalų mišinys ir padidinta vandenilio energijos dalis užtikrina degimo intensyvumą degimo proceso pradžioje ir sutrumpina uždegimo gaišties trukmę. AVL BOOST modeliavimas, atliktas plačiu vandenilio energijos dalies diapazonu (16–80 %), patvirtino teiginį, kad degimas tampa intensyvesnis degimo pradžioje dėl padidinto vandenilio kiekio. Didinant vandenilio kiekį, buvo pastebėta, kad išmetamosiose dujose sumažėjo CO, CO2 ir kietųjų dalelių, tačiau padidėjo NO koncentracija.

Fast-Burn Combustion Chamber Design for Natural Gas Engines

1998 ◽  
Vol 120 (1) ◽  
pp. 232-236 ◽  
Author(s):  
R. L. Evans ◽  
J. Blaszczyk
Keyword(s):  
Combustion Chamber ◽  
Engine Performance ◽  
Fuel Mixture ◽  
Performance Parameters ◽  
Combustion Chambers ◽  
Natural Gas Engines ◽  
Chamber Design ◽  
Performance And Emissions ◽  
Unburned Hydrocarbons ◽  
Fuel Mixtures

The work presented in this paper compares the performance and emissions of the UBC “Squish-Jet” fast-burn combustion chamber with a baseline bowl-in-piston (BIP) chamber. It was found that the increased turbulence generated in the fastburn combustion chambers resulted in 5 to 10 percent faster burning of the air–fuel mixture compared to a conventional BIP chamber. The faster burning was particularly noticeable when operating with lean air–fuel mixtures. The study was conducted at a 1.7 mm clearance height and 10.2:1 compression ratio. Measurements were made over a range of air–fuel ratios from stoichiometric to the lean limit. At each operating point all engine performance parameters, and emissions of nitrogen oxides, unburned hydrocarbons, and carbon monoxide were recorded. At selected operating points a record of cylinder pressure was obtained and analyzed off-line to determine mass-burn rate in the combustion chamber. Two piston designs were tested at wide-open throttle conditions and 2000 rpm to determine the influence of piston geometry on the performance and emissions parameters. The UBC squish-jet combustion chamber design demonstrates significantly better performance parameters and lower emission levels than the conventional BIP design. Mass-burn fraction calculations showed a significant reduction in the time to burn the first 10 percent of the charge, which takes approximately half of the time to burn from 10 to 90 percent of the charge.

Optimal Design of a Two-Stroke Diesel Engine for Aeronautical Applications Concerning Both Thermofluidynamic and Acoustic Issues

2008 ◽  
Author(s):  
Daniela Siano ◽  
Michela Costa ◽  
Fabio Bozza
Keyword(s):  
Diesel Engine ◽  
Acoustic Analysis ◽  
Fluid Dynamic ◽  
Combustion Process ◽  
Engine Performance ◽  
Combustion Noise ◽  
Process Efficiency ◽  
Injection System ◽  
Common Rail Injection System ◽  
First Choice

Some aspects concerning the development of a prototype of a diesel engine suitable for aeronautical applications are discussed. The engine aimed at achieving a weight to power ratio equal to one kg/kW (220 kg for 220 kW) is conceived in a two stroke Uniflow configuration and constituted by six cylinders distributed on two parallel banks. Basing on a first choice of some geometrical and operational data, a preliminary fluid-dynamic and acoustic analysis is carried out at the sea level. This includes the engine-turbocharger matching, the estimation of the scavenging process efficiency, and the simulation of the spray and combustion process, arising from a Common Rail injection system. Both 1D and 3D CFD models are employed. In-cylinder pressure cycles are utilized to numerically predict the combustion noise. The acoustic study is based on the integration of FEM/BEM codes. In order to improve the engine performance and vibro-acoustic behaviour, the 1D model, tuned with information derived from the 3D code, is linked to an external optimiziation code (ModeFRONTIER™). A constrained multi-objective optimization is performed to contemporary minimize the fuel consumption and the maximum in-cylinder temperature and pressure gradient. In this way a better selection of a number of engine parameters is carried out (exhaust valve opening, closing and lift, intake ports heights, start of injection, etc). The best found solution is finally compared to the initial one and some substantial design improvements are discussed.

Investigation on the Match between the Nozzle Tip Penetration and the Double-Layers Diffluent Combustion Chamber Geometry

2013 ◽  
Vol 860-863 ◽  
pp. 1738-1743
Author(s):  
Kun Peng Qi ◽  
Ming Hai Li ◽  
Wu Qiang Long
Keyword(s):  
Diesel Engine ◽  
Combustion Chamber ◽  
Fuel Injection ◽  
Combustion Process ◽  
Fuel Mixture ◽  
Injection System ◽  
Double Layers ◽  
Cylinder Pressure ◽  
Combustion System ◽  
Ratio Distribution

In order to investigate the match between the nozzle tip penetration and the double-layers diffluent combustion chamber geometry, a simulation model was developed which was based on the 135 diesel engine to simulate the equivalence ratio distribution of air-fuel mixture and the temperature distribution during combustion process. At the same time, an experiment was executed by a 135 diesel engine equipped with the high-pressure common rail fuel injection system. The research results show that the air-fuel mixture becomes more uniformed and the combustion process is improved when the nozzle tip penetration is reasonable selected which lead to higher in-cylinder pressure and better brake specific fuel consumption while NOXemission is increased and soot emission is decreased for the double-layers diffluent combustion system.

scholarly journals Combustion Thermodynamics of Ethanol, n-Heptane, and n-Butanol in a Rapid Compression Machine with a Dual Direct Injection (DDI) Supply System

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2729
Author(s):  
Ireneusz Pielecha ◽  
Sławomir Wierzbicki ◽  
Maciej Sidorowicz ◽  
Dariusz Pietras
Keyword(s):  
Heat Release ◽  
Combustion Chamber ◽  
Internal Combustion Engines ◽  
Direct Injection ◽  
Combustion Process ◽  
Combustion Efficiency ◽  
Injection System ◽  
Rapid Compression Machine ◽  
Process Indicators ◽  
Rapid Compression

The development of internal combustion engines involves various new solutions, one of which is the use of dual-fuel systems. The diversity of technological solutions being developed determines the efficiency of such systems, as well as the possibility of reducing the emission of carbon dioxide and exhaust components into the atmosphere. An innovative double direct injection system was used as a method for forming a mixture in the combustion chamber. The tests were carried out with the use of gasoline, ethanol, n-heptane, and n-butanol during combustion in a model test engine—the rapid compression machine (RCM). The analyzed combustion process indicators included the cylinder pressure, pressure increase rate, heat release rate, and heat release value. Optical tests of the combustion process made it possible to analyze the flame development in the observed area of the combustion chamber. The conducted research and analyses resulted in the observation that it is possible to control the excess air ratio in the direct vicinity of the spark plug just before ignition. Such possibilities occur as a result of the properties of the injected fuels, which include different amounts of air required for their stoichiometric combustion. The studies of the combustion process have shown that the combustible mixtures consisting of gasoline with another fuel are characterized by greater combustion efficiency than the mixtures composed of only a single fuel type, and that the influence of the type of fuel used is significant for the combustion process and its indicator values.

scholarly journals Jet A and Propane gas combustion in a turboshaft engine: performance and emissions reductions

2021 ◽  
Vol 3 (4) ◽  
Author(s):  
Ali Hasan ◽  
Oskar J. Haidn
Keyword(s):  
Combustion Process ◽  
Engine Performance ◽  
Emissions Reductions ◽  
Gas Combustion ◽  
Liquid Petroleum Gas ◽  
Performance And Emissions ◽  
Air Mixing ◽  
Turboshaft Engine ◽  
Engine Performance And Emissions ◽  
Lower Carbon

AbstractThe Paris Agreement has highlighted the need in reducing carbon emissions. Attempts in using lower carbon fuels such as Propane gas have seen limited success, mainly due to liquid petroleum gas tanks structural/size limitations. A compromised solution is presented, by combusting Jet A fuel with a small fraction of Propane gas. Propane gas with its relatively faster overall igniting time, expedites the combustion process. Computational fluid dynamics software was used to demonstrate this solution, with results validated against physical engine data. Jet A fuel was combusted with different Propane gas dosing fractions. Results demonstrated that depending on specific propane gas dosing fractions emission reductions in ppm are; NOx from 84 to 41, CO2 from less than 18,372 to less than 15,865, escaping unburned fuels dropped from 11.4 (just Jet A) to 6.26e-2 (with a 0.2 fraction of Propane gas). Soot and CO increased, this is due to current combustion chamber air mixing design.

scholarly journals Numerical Study of Engine Performance and Emissions for Port Injection of Ammonia into a Gasoline\Ethanol Dual-Fuel Spark Ignition Engine

2021 ◽  
Vol 11 (4) ◽  
pp. 1441
Author(s):  
Farhad Salek ◽  
Meisam Babaie ◽  
Amin Shakeri ◽  
Seyed Vahid Hosseini ◽  
Timothy Bodisco ◽  
...  
Keyword(s):  
Numerical Study ◽  
Combustion Process ◽  
Engine Performance ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Combustion Model ◽  
Dual Fuel ◽  
Spark Ignition Engines ◽  
Performance And Emissions ◽  
Hc Emissions

This study aims to investigate the effect of the port injection of ammonia on performance, knock and NOx emission across a range of engine speeds in a gasoline/ethanol dual-fuel engine. An experimentally validated numerical model of a naturally aspirated spark-ignition (SI) engine was developed in AVL BOOST for the purpose of this investigation. The vibe two zone combustion model, which is widely used for the mathematical modeling of spark-ignition engines is employed for the numerical analysis of the combustion process. A significant reduction of ~50% in NOx emissions was observed across the engine speed range. However, the port injection of ammonia imposed some negative impacts on engine equivalent BSFC, CO and HC emissions, increasing these parameters by 3%, 30% and 21%, respectively, at the 10% ammonia injection ratio. Additionally, the minimum octane number of primary fuel required to prevent knock was reduced by up to 3.6% by adding ammonia between 5 and 10%. All in all, the injection of ammonia inside a bio-fueled engine could make it robust and produce less NOx, while having some undesirable effects on BSFC, CO and HC emissions.

Enhanced Splash Models for High Pressure Diesel Sprays

2006 ◽  
Author(s):  
L. Allocca ◽  
L. Andreassi ◽  
S. Ubertini
Keyword(s):  
Diesel Engines ◽  
Second Harmonic ◽  
Laser Sheet ◽  
Combustion Process ◽  
Numerical Data ◽  
Ccd Camera ◽  
Operating Conditions ◽  
Injection System ◽  
Correct Operation ◽  
Common Rail Injection System

Mixture preparation is a crucial aspect for the correct operation of modern DI Diesel engines as it greatly influences and alters the combustion process and therefore, the exhaust emissions. The complete comprehension of the spray impingement phenomenon is a quite complete task and to completely exploit the phenomenon a mixed numerical-experimental approach has to be considered. On the modeling side, several studies can be found in the scientific literature but only in the last years complete multidimensional modeling has been developed and applied to engine simulations. Among the models available in literature, in this paper, the models by Bai and Gosman [1] and by Lee et al. [2, 3] have been selected and implemented in the KIVA-3V code. On the experimental side, the behavior of a Diesel impinging spray emerging from a common rail injection system (injection pressures of 80 MPa and 120 MPa) has been analysed. The impinging spray has been lightened by a pulsed laser sheet generated from the second harmonic of a Nd-YAG laser. The images have been acquired by a CCD camera at different times from the start of injection (SOI). Digital image processing software has enabled to extract the characteristic parameters of the impinging spray with respect to different operating conditions. The comparison of numerical and experimental data shows that both models should be modified in order to allow a proper simulation of the splash phenomena in modern Diesel engines. Then the numerical data in terms of radial growth, height and shape of the splash cloud, as predicted by modified versions of the models are compared to the experimental ones. Differences among the models are highlighted and discussed.

scholarly journals Research on combustion process of gasoline homogenous charge compression ignition engine

2018 ◽  
Vol 184 ◽  
pp. 01013
Author(s):  
Corneliu Cofaru ◽  
Mihaela Virginia Popescu
Keyword(s):  
Experimental Research ◽  
Fuel Injection ◽  
Combustion Process ◽  
Fuel Mixture ◽  
Spark Ignition Engine ◽  
Injection System ◽  
Compression Ignition ◽  
Compression Ignition Engine ◽  
Engine Operation ◽  
Homogenous Charge Compression Ignition

The paper presents the research designed to develop a HCCI (Homogenous Charge Compression Ignition) engine starting from a spark ignition engine platform. The chosen test engine was a single cylinder, four strokes provided with a carburettor. The results of experimental research data obtained on this version were used as a baseline for the next phase of the research. In order to obtain the HCCI configuration, the engine was modified, as follows: the compression ratio was increased from 9.7 to 11.5 to ensure that the air – fuel mixture auto-ignite and to improve the engine efficiency; the carburettor was replaced by a direct fuel injection system in order to control precisely the fuel mass per cycle taking into account the measured intake air-mass; the valves shape were modified to provide a safety engine operation by ensuring the provision of sufficient clearance beetween the valve and the piston; the exchange gas system was changed from fixed timing to variable valve timing to have the possibilities of modification of quantities of trapped burnt gases. The cylinder processes were simulated on virtual model. The experimental research works were focused on determining the parameters which control the combustion timing of HCCI engine to obtain the best energetic and ecologic parameters.

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