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Bio-ketones from lignocellulosic biomass: experimental investigation on fuel properties, combustion and emissions characteristics of cyclopentanone blend with diesel in compression ignition engine

Doustdar O., Wyszynski M. L., Tsolakis A., Mahmoudi H.

Combustion Engines

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2017

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R. 56, nr 4

81--86

EN

Use of alternative fuels in compression ignition engines is the topic for many studies. This paper presents the results of lubricity, calorific value, viscosity, surface tension and density of a ketone blend with diesel to use as a fuel in compression ignition engine. Analyses of fuel properties are vital due to their effect on fuel system. In addition, this study is related to the development of future biofuels and it indicates the effect of oxygen double bond in molecular structure of ketones on important fuel properties. Cyclopentanone which has cyclic molecular structure was used; it can be produced from lignocellulosic biomass through various processing ways. This ketone was blended with diesel fuel at 10% vol. Results from fuel properties tests were compared to the conventional diesel fuel. In the next step this blend was tested in a research diesel engine to analyse its combustion behaviour and emission characteristics of exhaust gases; these results were compared with ultra-low sulphur diesel fuel. Results showed that cyclopentanone, as an additive to diesel, improved surface tension and density of the fuel but in contrast had negative effect on viscosity, lubricity and calorific value of the fuel, but still in the standard range. Combustion behaviour of this fuel in the diesel engine also showed longer ignition delay of ketone blend and also that gaseous emission such as CO and THC are higher than from diesel fuel and NOx emission is less than from conventional diesel fuel combustion.

2

Performance of a drop-in biofuel emulsion on a single-cylinder research diesel engine

Bogarra-Macias M., Doustdar O., Fayad M. A., Wyszyński M. L., Tsolakis A., Ding P., Pacek A., Martin P., Overend R., O'Leary S.

Combustion Engines

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2016

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R. 55, nr 3

9--16

EN

Current targets in reducing CO2 and other greenhouse gases as well as fossil fuel depletion have promoted the research for alternatives to petroleum-based fuels. Pyrolysis oil (PO) from biomass and waste oil is seen as a method to reduce life-cycle CO2, broaden the energy mix and increase the use of renewable fuels. The abundancy and low prices of feedstock have attracted the attention of biomass pyrolysis in order to obtain energy-dense products. Research has been carried out in optimising the pyrolysis process, finding efficient ways to convert the waste to energy. However, the pyrolysis products have a high content in water, high viscosity and high corrosiveness which makes them unsuitable for engine combustion. Upgrading processes such as gasification, trans-esterification or hydro-deoxynegation are then needed. These processes are normally costly and require high energy input. Thus, emulsification in fossil fuels or alcohols is being used as an alternative. In this research work, the feasibility of using PO-diesel emulsion in a single-cylinder diesel engine has been investigated. In-cylinder pressure, regulated gaseous emissions, particulate matter, fuel consumption and lubricity analysis reported. The tests were carried out of a stable non-corrosive wood pyrolysis product produced by Future Blends Ltd of Milton Park, Oxfordshire, UK. The product is trademarked by FBL, and is a stabilized fraction of raw pyrolysis oil produced in a process for which the patent is pending. The results show an increase in gaseous emissions, fuel consumption and a reduction in soot. The combustion was delayed with the emulsified fuel and a high variability was observed during engine operation.

3

The study of simulated biogas on combustion and emission characteristics in compression ignition engines

Tira H. S., Gili S. S., Theinnoi K., Shenker J., Lau C. S., Tsolakis A., Dearn K., Turner D., Wyszyński M. L.

Silniki Spalinowe

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2010

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R. 49, nr 2

47-55

EN

New renewable fuels have been developed for diesel engines, contributing to the reduction of carbon emissions and to fuel security. However, the combustion characteristics of these fuels and emissions still remain unclear. A study to investigate diesel engine performance integrated with biogas and hydrogen has been carried out. Biogas is principally a mixture of methane (CHJ and carbon dioxide (CO J along with other trace gases. In this study the simulated gaseous biogas (60% CH4 and 40% CO2 vol.) and hydrogen (2% vol.) fuels were fed into the engine intake manifold and diesel fuel was injected into cylinder as a pilot ignition fuel. The effects of biogas and hydrogen showed reduced PM compared with diesel combustion. In addition, up to 39 and 33% reduction in total particulate mass and smoke, respectively, was seen. However, there was a slight increase in particle number when gaseous fuel addition was used, where the particulate size distributions have moved towards the nucleation region thus benefitting the after-treatment systems. Reduced thermal efficiency was observed for the gaseous fuel addition.

PL

Nowe odnawialne paliwa dla silników o zapłonie samoczynnym (ZS) przyczyniają się do zmniejszenia emisji dwutlenku węgla oraz do poprawy bezpieczeństwa zaopatrzenia w paliwa. Jednakże charakterystyki spalania tych paliw oraz ich właściwości emisyjne nie są wciąż w pełni zbadane. W artykule przedstawiono wyniki badań osiągów silnika ZS zasilanego w układzie podwójnym: olejem napędowym oraz biogazem i wodorem. Biogaz jest mieszaniną głównie metanu (CHJ i dwutlenku węgla (COJ oraz śladowych ilości innych gazów. W przedstawionych badaniach stosowano symulowany (syntetyczny) biogaz, zawierający 60% CH4 i 40% CO2 Paliwa gazowe dostarczane były do kolektora dolotowego silnika, a paliwo ciekłe (olej napędowy) było wtryskiwane do cylindra jako dawka zapłonowa. Efektem zastosowania biogazu i wodoru było obniżenie emisji cząstek stałych w porównaniu ze spalaniem czystego oleju napędowego. Zaobserwowano obniżoną masową emisję cząstek stałych i zmniejszenie dymienia (odpowiednio o 39 i 33%). Przy użyciu paliwa gazowego zaobserwowano także nieznaczne zmiany liczby cząstek stałych, przy czym rozkład wymiarowy cząstek przesunął się w stronę obszaru nukleacyjnego, co jest korzystne z punktu widzenia sprawności układów oczyszczania spalin. Zastosowanie paliw gazowych spowodowało również zmniejszenie sprawności cieplnej silnika.

4

Combined Effects of Pilot Quantity, Injection Pressure and Dwell Periods on the Combustion and Emissions Behaviour of a Modern V6 Diesel Engine

Abdullah N. R., Wyszynski M. L., Tsolakis A., Mamat R., Xu H. M., Tian G.

Archivum Combustionis

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2010

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Vol. 30 nr 4

481-495

EN

Experimental results have shown that high exhaust emissions in diesel engines can be avoided by employing special injection strategies. This is because an increased homogeneity of the fuel-air mixture created by some injection strategies has a capability to improve NOx-PM trade-off. Therefore, the mixture quality is a primary parameter that needs to be controlled in order to enhance engine power output and low exhaust emissions. In fact, the combustion strategy employing multiple injections and EGR technique tends to introduce better fuel economy as well. In the experimental work presented in this paper the combinations of pilot quantities, injection pressures and dwell periods (time lapse between Pilot Injection Timing and Main Injection Timing) have been tested on a modern V6 diesel engine. The engine utilises a common rail direct injection, is fitted with twin turbo-charged variable turbine geometry (VTG) turbochargers and is fuelled with ultra low sulphur diesel (ULSD). The overall results show that these strategies have a potential to improve exhaust emissions specifically NOx, Particulate Matter, THCs, CO emissions and fuel economy.

5

Acidity of Tallow (Animal Fat) and Its Effect on Suitability of Tallow as Fuel in Electricity Generating Engines

Piaszyk J., Wyszynski M. L., Tsolakis A.

Archivum Combustionis

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2010

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Vol. 30 nr 4

471-480

EN

The paper outlines properties of tallow to be used as fuel, its production process and annual variation of the measured parameters – density, acidity, impurities, calorific value etc. Most of the parameters are constant throughout the year, except acidity. Acidity is high during the summer and low in winter – this is consistent with environmental temperature changes. High levels of free fatty acids are consistent with the perceived low quality of fat and are also responsible for the unpleasant bitter taste of rancid fat. Admissible acidity levels of fuel for the four- and two-stroke heavy fuel oil (HFO) engines indicate that in winter the two stroke engine may be used, but in the summer acidity levels are generally too high. Possible industrial methods of acidity reduction are briefly discussed.

6

The effect of injection pressure and strategy in a Jaguar V6 diesel engine

Abdullah N. R., Mamat R., Rounce P., Wyszynski M. L., Tsolakis A., Xu H. M., Tian G.

Journal of KONES

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2009

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Vol. 16, No. 2

9-22

EN

In recent years, the improvement of engine performance and emissions has become an extremely important concern. This study focuses on the injection strategy based on the injection pressure (IP) and duration between pilot injection and the main injection (dMI) using a multi cylinder common rail multiple injections diesel engine. The study was designed to produce improvements in fuel mixing via the injection strategy, to reduce the main ignition delay. This would contribute to a minimum amount of fuel burnt in the premixed combustion phase, leading to a reduction in emissions. Recent evidence shows that premixed combustion is significant in the controlling of emissions of nitrogen oxides (NOx) and soot. Six different IPs combined with a short and long dMI were compared in the attempt to improve engine performance and emissions. The engine performance was measured in terms of brake specific fuel consumption, ignition delay, heat release and peak in-cylinder pressure and emissions, specifically nitrogen oxides (NOx), total unburned hydrocarbons (THC), carbon monoxide (CO) and smoke emissions for each engine test condition. The evidence from this study shows that the effect of IP is more dominant than dMI in terms of peak cylinder pressure, heat release, brake specific fuel consumption and emissions. However, the dMI shows a strong effect at a higher engine speed.

7

Boosted HCCI operation on multi cylinder V6 engine

Misztal J., Wyszyński M., Xu H., Tsolakis A., Qiao J., Wyszyński M., Xu H., Tsolakis A., Qiao J., Wilson T.

Journal of KONES

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2006

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Vol. 13, No. 2

315-321

EN

This paper is an extension of work done with boosted 1-cyl Homogenous Charge Compression Ignition (HCCI) engine. As has been proven in the authors’ laboratory on a single cylinder research engine, applying boosting can enable an increased load range with a decreased NOx emission. During the tests which are covered in this paper, a Jaguar V6 research engine with a negative valve overlap facility has been used. The engine is equipped with a mechanically coupled supercharger, which supplies the required amount of air. The introduction of a higher amount of air allows the cylinder mixture to be kept on a highly diluted level; this enables autoignition to be controlled and improves NOx emission. Finally, more air introduced into the cylinder enables more fuel to be injected, which in turn provides for a higher load. This fact is useful as one method to increase the upper load limit for HCCI. Boosted HCCI operation is very sensitive to exhaust gas residuals. It has been proven that valve operation, whether advancing or retarding away from the optimum point will affect NOx emission. Th6is paper will demonstrate that the optimisation of valve timing in connection with lambda value and boost pressure can produce lower NOx emission for the same or even a higher load.

8

An investigation of the presence of uncontrolled combustion phenomenon in spark ignition single cylinder optical engine

Luszcz P., Xu H., Wyszynski M., Tsolakis A., Frąckowiak M.

Journal of KONES

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2006

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Vol. 13, No. 2

281-290

EN

The objective of this paper is to investigate appearance of surface ignition - postignition experienced inside the engine cylinder and correlate it with the nature of the spark ignition combustion prior to the onset of surface ignition. The test engine used to carry out all experiments was a Jaguar optical single-cylinder engine, operating in spark-ignition mode, although with negative valve overlap. The optical configuration of the engine allows characterizing and analyzing combustion process based on the processing of captured images in correlation with in-cylinder pressure and other parameters recorded with regard to instantaneous engine operating conditions. Results of the experiments covered in this publication focus on flame propagation and development as well as reveal occurrence of abnormal combustion processes. Experimental observations, especially the captured images show a relationship between the nature of normal combustion process initiated by spark discharge and the existence of abnormal combustion phenomena. All tests were performed under fixed engine conditions - constant speed and single component hydrocarbon fuel. Because the nature of fuel can shape the combustion process, a brief discussion and a proposed correlation of anti-knock, auto-ignition, and resistance to surface ignition qualities of a few single- and multi-component fuels is presented. Finally the publication leads to provide an indication of possible solutions concerning the problem of uncontrolled post-ignition events in optical engines.