Wyniki wyszukiwania - Biblioteka Nauki

1

Alternative fuels and technologies for compression ignition internal combustion engines

100%

Bereczky A.

Journal of KONES

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2012

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tom Vol. 19, No. 4

43-51

EN

The traditional use of fossil-based fuels is now widely considered unsustainable because of depleting their natural resources. Potential substitutes of fossil fuels are oils of renewable origin such as various vegetable and non-edible oils. The aim of using these oils or their methyl esters (biodiesel) is to establish and maintain a balance between agriculture, economy and environment protection. However, realizing the increasing demand of raw materials currently used can be achieved not only by increasing the production area but also by introducing new materials or technologies. The article presents and evaluates modern raw fuel components that are currently being investigated. Furthermore, the article deals with the dual fuel combustion technology in detail, with which the processed fuels are becoming available for use in Compression Ignition (CI) engines, where conventional blending is difficult or their use exclusively in diesel engines is economically unjustified. In case of dual fuel engine systems, the primary fuel, such as (wet)ethanol, methanol, LPG, H2 etc. is injected into the intake manifold of the engine and the premixed mixture simultaneously produced is ignited by the pilot diesel fuel as secondary fuel injected directly into the engine cylinder. This technology can significantly reduce exhaust emissions and can slightly increase engine efficiency. The achievements in this field and recently obtained results by the author and his research group are also presented. Exhaust emissions, performance and combustion characteristics were measured and analyzed with respect to several operating parameters as follows: premixed ratio (rp), pilot timing and engine load.

2

Comparison of the environmental impacts of a plug-in hybrid and a full electric car using life cycle assessment

63%

Szilágyi A. , Bereczky A.

Journal of KONES

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2018

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tom Vol. 25, No. 2

363--369

EN

Full electric (FEV) and plug-in hybrid (PHEV) vehicles are promising, forward-looking technologies to reduce greenhouse gas (GHG) emissions and other pollution related to road transport. The powertrain of a FEV is composed of a battery, control electronics and the electric motors. A PHEV has much lower battery capacity but it contains an extra internal combustion engine and gearbox. Many argue that FEVs are more energy-efficient than internal combustion engines. However, this energy needs to be stored in heavy, large-capacity battery packs that require plenty of energy and resources to produce as well as highly polluting rare earth elements mining. In this article, an environmental comparison of FEVs and PHEVs is shown using life cycle assessment (LCA). To make the comparison realistic, two models similar in size and power have been selected: Volkswagen E-Golf FEV and Volkswagen GTE PHEV. Results show that the production of FEVs need more energy and it means more burden on the environment however during the use phase it causes less emissions. Since the local electricity production mix and, in case of PHEVs, the user behaviour highly affects the results, three different countries (Hungary, Poland and Norway) and two different use types are considered. The quantified environmental footprints as well as the break-even distances are presented. Sensitivity of the results towards the assumed conditions during the whole design lifetime of the vehicles is discussed.

3

Use of biofuels in a compression-ignition engine : comprehensive technical and economical analysis

63%

Szabados G. , Bereczky A.

Journal of KONES

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2018

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tom Vol. 25, No. 1

385--393

EN

The assessment of renewable fuels on the basis of the results of internal combustion engine’s tests is not clearly good or not good. Biofuels can be a part of sustainability from energy sources, energy security and energy diversity point of view. But they cannot be assessed better compared to the fossil diesel as for their combustion and air pollution and the engine’s external parameters. Comparison test series has been conducted with three different fuel and their controlled blends. These fuels were fossil diesel, the conventional, standardized biodiesel, and a new type biodiesel, which is the so-called TBK-biodiesel. These tests covered the physicochemical properties of the fuels, the engine external parameters, the combustion parameters and the exhaust emission of an internal combustion compression ignition engine. Furthermore, external costs have been calculated based on the emission results. Physicochemical properties, engine parameters, combustion parameters, exhaust emission and external costs have been observed as parameter groups, which contain many parameters. A complex evaluation could be built with the help of such kind of parameter set. On the basis of the results, it can be established that almost in the most cases the direction of the parameters’ changes is negative. Thus, the evaluation’s centre of gravity has been observed as shifted in the negative direction.

4

Biogas utilization in an internal combustion engine working in a serial hybrid propulsion system

51%

Kovacs V. B. , Torok A. , Bereczky A. , Szwaja S.

Silniki Spalinowe

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2012

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tom R. 51, nr 1

17-24

EN

Due to increase in demand for fossil fuels and aspects of natural environment protection, there is a major need to utilize alternative and renewable energy sources in order to promote sustainable development. The use of biogas as a source of renewable energy could provide effective and alternative way to satisfy a remarkable part of this demand for the transportation sector. As biogas has high inert content of carbon dioxide, its heating value is lower compared to CNG. Applying these low heating value renewable gaseous fuels for means of transport is not fully worked out yet because their combustion characteristics significantly differ from liquid fuels that are currently used or propane, or natural gas based systems that are becoming more and more popular in transportation. Biogas is not in common use, thus its utilization is recently limited for engines with conventional equipment burning other fuels. Thus, theoretical and experimental analysis was made to investigate the usability of biogas. On the basis of conducted investigation, it was found that effective biogas utilization as a fuel for means of transport can be achieved in a serial hybrid system consisted of internal combustion reciprocating engine.

PL

Potrzeba zagospodarowywania alternatywnych źródeł energii, w tym źródeł odnawialnych, stymulowana jest koniecznością zaspokojenia narastającego zapotrzebowania na paliwa kopalne oraz ochroną środowiska naturalnego. Wykorzystanie biogazu jako źródła energii odnawialnej może być skutecznym a także alternatywnym środkiem do zaspokojenia znaczącej części tego zapotrzebowania na potrzeby sektora transportu. Biogaz, w porównaniu do CNG, charakteryzuje się mniejszą wartością opałową z powodu występowania w nim dużej ilości składnika niepalnego, jakim jest dwutlenek węgla. Wykorzystanie tego niskokalorycznego paliwa gazowego na potrzeby środków transportu nie jest jeszcze w pełni naukowo zbadane z powodu znaczących różnic w zakresie przebiegu spalania w porównaniu do propanu, metanu lub paliw ciekłych. Pomimo tego paliwa te stają się coraz bardziej popularne w sektorze transportu. Obecnie biogaz nie jest jeszcze powszechnie stosowany, dlatego jego wykorzystanie jako paliwa trakcyjnego jest ograniczane do klasycznych silników tłokowych standardowo spalających inne paliwa. Zatem w celu zbadania przydatności biogazu jako paliwa trakcyjnego przeprowadzono analizę teoretyczną i badania eksperymentalne. Na podstawie przeprowadzonych badań uznano, że efektywne wykorzystanie biogazu jako paliwa do środków transportu można osiągnąć w wyniku jego spalania w szeregowym, hybrydowym zespole napędowym zawierającym tłokowy silnik spalinowy.

5

Experimental analysis of noise and vibration of a diesel engine

38%

Kilikevičienė K. , Fursenko A. , Kilikevičius A. , Vainorius D. , Matijošius J. , Rimkus A. , Bereczky A.

Journal of KONES

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2018

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tom Vol. 25, No. 1

225-232

EN

Noise and vibration of ignition compression engine is one of the most complicated fields to cope with since every mechanism that compose of the engine affect them separately. In this study, effect of diesel on engine noise and vibration has been studied on an unmodified compression ignition engine. Noise and vibration characteristic of a direct ignition engine, which was fuelled with diesel, were investigated. With the usage of equations obtained from regression analysis, estimation of engine characteristic fuelled with various biodiesels researches were carried out. Tests were conducted at fixed injection timing of diesel fuel. The first system is for diesel fuel injection; the second one is PFI (port-fuelled injection) and is used for injecting alcohol into the engine intake manifold. The engine applied to this study was a naturally aspirated, 3in-line, IVECO AIFO 8031 i06.05 diesel engine with direct injection. Experiments were conducted in a sound insulated room. For each experiment, vibration data gathered from the engine block with 3.2 kHz (for vibration) for 2 s and with 20 kHz sampling frequency for 0.320 s. All measurements were performed under conditions: angle 10; 4 different loads (4, 8, 12 and 20 kW).