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1

Relative Change in SI Engine Performance Using Hydrogen and Alcohol as Fuel Supplements to Gasoline

Yamin Jehad A.A., Sheet Eiman Ali Eh, Rida Khalid S.

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no 1

144--145

EN

A simulation study on the effect of hydrogen and ethanol addition as supplementary fuel for gasoline engine at lean mixture (equivalence ratio ϕ = 0.8) was carried out to reduce the gasoline share in the mixture, thus reducing the fuel consumption and harmful emissions. The effect of supplementary fuels on engine performance, emissions, and availability was investigated. This was done by changing the ratio between gasoline and the supplementary fuels in the fuel mixture to achieve the required equivalence ratio. The first part of the simulation consisting of the performance and emissions calculated using the first law, was conducted for all engine speeds. The second part consisting of an availability analysis was conducted at the rated speed of 2750 rpm. The simulation study was conducted using the data obtained from measurements of Ricardo E6/T engine parameters (variable compression ratio engine). The data was also used to verify the models. The study shows that the hydrogen addition reduced the carbon monoxide (CO) and nitrogen oxides (NO2) share at the lean mixture. The hydrogen addition significantly improved the heat release rate compared with pure gasoline; however, the heat released was close to the top dead center due to its fast burning speed. The ethanol addition improved the first law performance of the engine, e.g., power and efficiency; however, at the cost of increased heat loss. It also improved the indicated work availability in comparison with the addition of hydrogen.

2

Uproszczony opis kinetyki spalania metanu w powietrzu w pobliżu punktu stechiometrycznego w odniesieniu do strumienia molowego

Kędzior R., Grzesiak D., Popławski D., Hałat A., Głowiński J.

Przemysł Chemiczny

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2015

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T. 94, nr 6

948-951

PL

Przedstawiono uproszczony opis kinetyczny spalania metanu w powietrzu w pobliżu punktu stechiometrycznego po stronie mieszanek ubogich w paliwo. Bazując na wynikach symulacji spalania metanu, wyznaczono parametry proponowanych równań kinetycznych.

EN

The model of Warnatz mechanismus of the reaction and a com. computer program were used to simulate the combustion of MeH-air mixts. (MeH content 9.14–9.50% by vol.) to est. the parameters of the reaction kinetic equations.

3

Badania silnika spalinowego ZI zasilanego gazem ziemnym do zastosowań w mikrokogeneracji

Przybyła G., Postrzednik S.

Instal

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2014

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nr 5

14--19

PL

W artykule przedstawiono wyniki badań eksperymentalnych silnika spalinowego o zapłonie iskrowym, zasilanego stechiometryczną oraz ubogą mieszanką gazu ziemnego z powietrzem. Przeprowadzono obliczenia wartości opałowej mieszanki gazowo-powietrznej w szerokim zakresie zmienności stosunku nadmiaru powietrza. Badaniom podlegał silnik spalinowy małej mocy. Standardowo ten typ silnika stosowany jest w przemyśle motoryzacyjnym, a ze względu na niską cenę zakupu oraz koszty eksploatacji może znaleźć zastosowanie w układach kogeneracyjnych małej mocy. Głównym celem niniejszej pracy jest określenie parametrów energetycznych silnika oraz jego oddziaływania na środowisko podczas spalania mieszanek ubogich gazu ziemnego. Zaobserwowano wyraźny wpływ stosunku nadmiaru powietrza na parametry energetyczne oraz ekologiczne silnika spalinowego zasilanego gazem ziemnym GZ50. Wartość sprawności energetycznej wzrasta niespełna o ok. 2 punkty procentowe przy zmianie wartości stosunku nadmiaru powietrza od mieszanki stechiometrycznej do wartości λ=1,5.

EN

In this paper the experimental results of SI engine fuelled with lean mixture of natural gas are presented. the calculations of the calorific value of air-gas mixtures in a wide range of the excess air ratio variation has been done.The experiments were carried out on the petrol engine with a low engine displacement. Typical SI engine was selected in order to evaluate the potential application of gaseous fuel (i.e. natura gas). These types of engines are available on a wide scale and commonly used in automotive sector because of the low purchase price and operating costs. It is expected that after minor modifications, the engine can easily operate in micro CHP system. The main goal of this work is to determine the performance of the engine and its impact on the environment during the combustion of the lean natural gas mixtures. There was a clear effect of excess air ratio on the performance and environmental impact of internal combustion engine powered by natural gas GZ50. The engine efficiency increase about 2 percentage points when changing the value of the excess air ratio of the mixture to the stoichiometric λ=1.5.

4

Analiza procesu spalania ubogich mieszanek paliw gazowych w silniku ZI

Przybyła G., Postrzednik S., Żmudka Z.

Combustion Engines

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2013

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R. 52, nr 3

371--378

PL

W artykule przedstawiono wyniki badań teoretycznych i eksperymentalnych silnika spalinowego o zapłonie iskrowym, zasilanego ubogimi mieszankami gazu z powietrzem. Przeprowadzono obliczenia wartości opałowej mieszanki gazowo-powietrznej (ed,v) dla wybranych paliw gazowych (gaz ziemny, biogaz, gaz z procesów zgazowania paliw stałych). Na podstawie własności tych paliw, określona została sprawność teoretycznego obiegu Otto, stosując zmienne wartości nadmiaru powietrza. Badania przeprowadzono na silniku o niskiej objętości skokowej. Tego typu silniki są stosowane w przemyśle motoryzacyjnym, a ze względu na niską cenę zakupu oraz koszty eksploatacji mogą być stosowane w układach kogeneracyjnych małej mocy. Głównym celem niniejszej pracy jest określenie parametrów silnika spalinowego ZI podczas spalania mieszanek ubogich. Jak wykazała analiza, największa różnica w wartościach (ed,v) energii chemicznej mieszanki palnej dla analizowanych paliw występuje w zakresie mieszanek stechiometrycznych. W tym miejscu różnica Δ ed,v pomiędzy gazem ziemnym, a przykładowym gazem ze zgazowania biomasy wynosi ok. 35%, podczas gdy w zakresie mieszanek ubogich różnica ta jest znacznie niższa. Dla bardzo wysokich wartości stosunku nadmiaru powietrza λ wspomniana różnica osiąga wartość „0”. Zaobserwowano wyraźny wpływ stosunku nadmiaru powietrza na nierównomierność pracy silnika bazującego na średnim ciśnieniu indykownym (COVIMEP). Wartości tego wskaźnika rosną ze wzrostem stosunku nadmiaru powietrza. Uzyskane wyniki kształtują się na dopuszczalnym poziomie ze względu na zastosowanie silnika w układzie CHP i osiągają wartość poniżej 5%.

EN

In this paper the results of the theoretical and experimental study of an internal combustion engine, fuelled with lean air – gas mixtures, are presented. Calorific value of air-fuel mixture were calculated for several chosen gaseous fuels such as: natural gas, landfill gas, and producer gas. Based on these fuels, the performance of a theoretical Otto cycle was investigated using variable air excess values. The experiments were carried out on a petroleum engine with a low engine displacement. A typical SI engine was selected in order to evaluate the potential application of a gaseous fuel (i.e. natural gas). These types of engines are widely available and commonly used in the automotive sector because of low purchase prices and operating costs. It is expected that after minor modifications, the engine can easily operate in a low power co-generation mode. The main objective is to evaluate the performance of the engine under lean air/fuel mixture conditions. The analysis shows that the most significant difference in the calorific value of air fuel mixture (ed,v) for chosen fuels is occured for stoichiometric mixtures. At this point the difference Δ ed,v between natural gas and the producer gas is about 35%, while for the lean mixtures the difference is much less. The slight impact of air excess ratio on COVIMEP was noticed. The value decreases insensibly with air excess ratio decreasing. Obtained results are located at acceptable levels for power generation sources and are less than 5 %.

5

Energy analysis of a small capacity SI engine fueled with lean air gas mixture

Przybyła G., Postrzednik S., Żmudka Z.

Journal of KONES

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2012

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Vol. 19, No. 2

423-432

EN

In this paper, the results of the theoretical study of an internal combustion engine, fuelled with lean air - gas mixtures, are presented. Energetic property calculations were done for several chosen gaseous fuels such as methane, landfill gas, and producer gas. Based on these fuels, the performance of a theoretical Seiliger-Sabathe cycle was investigated using variable air excess values. The accurate analysis of the various processes taking place in an internal combustion engine is a very complex problem. If these processes were to be analyzed experimentally, it would be more expensive than theoretical analysis. The Seiliger-Sabathe cycle turns out to be help in theoretical analysis of internal combustion engine performance. Dimensionless descriptive parameters (E, psi) are very useful at this analysis by combining the properties of fuel with initial thermodynamic parameters of the cycle. Moreover, the experimental results of SI engine fuelled with a lean mixture of natural gas are presented for comparative purposes. The experiments were carried out on a petroleum engine with a low engine displacement. A typical SI engine was selected in order to evaluate the potential application of a gaseous fuel (i.e. natural gas). These types of engines are widely available and commonly used in the automotive sector because of low purchase prices and operating costs. It is expected that after minor modifications, the engine can easily operate in a low power co-generation mode. The main objective is to evaluate the performance of the engine under lean air/fuel mixture conditions. The slight impact of air excess ratio on COVIMEP was noticed. The value decreases insensibly with air excess ratio decreasing. Obtained results are located at acceptable levels for power generation sources and are less than 5 %. Although, the more distinct impact was observed regarding to COVpmax. The maximum value was noted for leaner mixture and it amounts to approximately 7.5%.

6

Analiza numeryczna obiegu cieplnego wieloświecowego silnika ZI

Sosnowski M., Kociszewski A., Jamrozik A., Tutak W.

Prace Naukowe Akademii im. Jana Długosza w Częstochowie. Edukacja Techniczna i Informatyczna

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2011

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T. 6

41-51

PL

W artykule przedstawiono wyniki trójwymiarowego modelowania procesu spalania w silniku ZI z zapłonem wielopunktowym. Porównano wyniki symulacji dla silnika z jedną, dwoma, trzema i czterema świecami zapłonowymi.

EN

3D modelling of combustion process in multi-spark plug SI engine is presented in the paper. Simulation results of engine with one, two, three and four spark plugs are compared.

7

Numerical modelling of combustion in SI engine fuelled with methane

Kociszewski A.

Silniki Spalinowe

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2009

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R. 48, nr 4

45-55

EN

Results of numerical analysis of methane and gasoline combustion in multipoint ignition SI engine are presented in the paper. Work parameters of engine fuelled with methane lean mixtures of λ = 1.45 and 1.8 for three configurations of spark plugs (one, two and four active spark plugs) are compared. These configurations were chosen taking into consideration earlier research concerning numerical modelling and experiments. The results of carried out analysis proved that using two spark plugs at air excess number λ = 1.8 caused that engine work parameters are similar to case of mixtures of λ = 1.45 with one spark plug configuration. Simultaneously, the emission of nitric oxide was decreased more than eight times and the concentration of carbon dioxide in exhaust gases was 20% lower.

PL

W artykule przedstawiono wyniki analizy numerycznej procesu spalania metanu w silniku ZI z zapłonem wielopunktowym. Porównano parametry pracy silnika zasilanego ubogimi mieszankami metanu o λ = 1,45 oraz 1,8 dla trzech konfiguracji świec zapłonowych: jedna, dwie oraz cztery pracujące świece zapłonowe. Konfiguracje te wybrano, biorąc pod uwagę wcześniejsze prace związane z modelowaniem oraz eksperymentem. Wyniki symulacji pokazały, że zastosowanie dwóch świec zapłonowych, przy współczynniku nadmiaru powietrza λ = 1,8, dało zbliżone parametry pracy silnika w porównaniu do zasilania mieszanką o λ = 1,45 z jedną świecą zapłonową. Jednocześnie otrzymano ponad ośmiokrotnie mniejszą emisję tlenku azotu oraz zmniejszoną o 20% zawartość dwutlenku węgla w spalinach modelu silnika.

8

Numerical analysis of spark plugs number influence on selected parameters of combustion in piston engine

Kociszewski A.

Silniki Spalinowe

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2008

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R. 47, nr 1

50-55

EN

The results of numerical analysis of combustion in multi-spark plug SI engine are presented in the paper. The outcome of computational analysis of lean mixtures combustion in engine with one and two spark plugs are compared. The output data was presented in graphical form as screenshots (temperature distribution) and as pressure and temperature courses in function of crank angle. 3D numerical modelling of combustion in multi-spark plug engine proved that improvement in lean mixture combustion process can be obtained by increasing the number of active ignition points. As conclusion it can be stated that numerical modelling results confirmed the favourable influence of applying two active spark plugs in lean mixtures combustion.

PL

W artykule przedstawiono analizę numeryczną procesu spalania w wieloświecowym silniku ZI. Porównano wyniki modelowania procesu spalania mieszanek zubożonych w silniku z jedną oraz dwoma świecami zapłonowymi. Dane wyjściowe zaprezentowano w postaci graficznej, jako slajdy (rozkład temperatury) oraz jako przebiegi ciśnienia w funkcji kąta obrotu wału korbowego. Modelowanie trójwymiarowe procesu spalania w silniku wieloświecowym pokazało, że zwiększenie liczby czynnych świec zapłonowych znacząco poprawia proces spalania mieszanek zubożonych. Główna wada tych mieszanek, jaką jest powolne, a wręcz przewlekłe spalanie została w dużym stopniu zniwelowana.

9

Study of NOx storage over the Pt/Rh-MgO/(CeO3)/Al3O3 catalyst

Księżopolska M., Darkowski A.

Journal of KONES

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2006

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Vol. 13, No. 2

249-257

EN

Preliminary studies of Pt/Rh-MgO/Al2O3 and Pt/Rh-MgO/CeO2/Al2O3 catalysts for storage and reduction of NOx in exhaust gases at rich and lean fuel mixture were performed. NOx conversion and time of reaching steady state for lean mixture was used for comparison of catalytic and sorption activity. Catalysts were prepared: first on the alumina pellets by impregnation process and second on steel honeycomb monolith with washcoat layer. The conversion of nitrogen oxides as a function of temperature and different time of lean period to rich was determined. Thanks to the results of these studies both catalysts were compared. The prepared bed reactor containing magnesia as NOxtrap oxidizes CO and HC and reduces NOx during cyclic changes of air to fuel mixtures. Oxidation and reduction properties of the reactor are strongly dependent on the cycle of mixture changes and temperature. Generally there is an average NOx conversion ratio decrease with the increase of lean period time. For monolith type of reactor Pt/Rh-MgO/CeO2/Al2O3 conversion didn not obtain acceptable results above 200oC for both SV values. The relation of the surface area to the volume of the reactor was higher for the monolith reactor than for the bed type.

10

Computational analysis and experimental research into lean mixture combustion in multi-spark plug SI engine

Kociszewski A., Jamrozik A., Sosnowski M., Tutak W.

Journal of KONES

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2006

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Vol. 13, No. 3

123-130

EN

Simulation and experimental research into combustion in multi-spark plug SI engine results are presented in the paper. The outcome of experiment and computational analysis of lean mixtures (excess air number values ? = 1.8) combustion in engine with one, four and seven spark plugs are compared. The results of both the numerical calculations and the experimental research confirmed that applying four spark plugs favourably influences the parameters of lean mixture combustion. The verification of mathematical model applied in KIVA-3V and the real engine was satisfying. The comparison of experimental and numerical research revealed good qualitative conformity of modelled pressure courses with pressure registered on real engine, and in the case of one spark plug the conformity was not only qualitative but also quantitative. The numerical simulations of combustion process reflects the phenomenon occurring in the combustion chamber of the research engine, which is confirmed by the case of seven spark plugs and its negative influence on combustion parameters of both the experimental and the model engines. The measurements results confirm the favourable influence of applying four spark plugs mostly in the case of lean mixture combustion.