Wyniki wyszukiwania - BazTech

1

Combustion process of direct injected water-coal mixture in diesel engine

Mitianiec W.

Combustion Engines

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2016

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R. 55, nr 1

37--43

EN

The paper describes the problem of coal-water mixture combustion process in heavy duty diesel engines in the energetic sector application. In the future due to depletion of crude oil resources we have to foreseen another fuel for application in power plants. Large deposits of coal and lignite in the world enable to utilize these fuels in different thermal machines, especially in internal combustion engines. A carbon powder containing small molecules about 10–20 micrometers dissolved in water is good fuel for applying in large capacity engines in electrical plants. Aqueous emulsion of coal has possibility of good cooling of injectors cooling and has also good lubricity. Initial experimental tests done in the world indicate a higher thermal efficiency of engine fuelled by water coal emulsion than engine fuelled by diesel oil and also gas turbine driven by gas from coal gasification technology. The increased emission of CO2 can be reduced in the plants simply by chemical reduction. The paper explains thermochemical processes taking place in the engines during combustion process. The work parameters results obtained from calculations were compared with those obtained from CI engine fuelled by diesel oil. The paper is a certain challenge for finding a new fuel sources as a competition for crude oil and allows to get acquainted with new engine fuelling technology.

2

Wymagania dotyczące obiektów zaplecza motoryzacyjnego w Polsce w zakresie zaopatrywania pojazdów w paliwa

Zielińska E.

TTS Technika Transportu Szynowego

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2015

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R. 22, nr 12

2211--2214, CD

PL

Treść artykułu dotyczy klasyfikacji i charakterystyki stacji paliw oraz zakresu usług oferowanych w stacjach osiedlowych, podstawowych i autostradowych. Określono kryteria dotyczące projektowania i użytkowania stacji paliw. Przedstawiono również obowiązujące wymagania w zakresie wyposażenia stacji paliw, ochrony środowiska oraz ochrony przeciwpożarowej.

EN

The content of the article are the classification and characterization of fuel stations. In this paper, the differences in the scope of services offered in the residential stations, core and highway are described. Listed requirements for the design and operation of service stations. Force requirements petrol station equipment, as well as guidelines for environmental protection and fire protection are presented.

3

Perspectives of applying of water-coal emulsion in heavy duty stationary diesel engines

Mitianiec W.

Combustion Engines

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2015

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R. 54, nr 3

744--751

EN

Large deposits of coal and lignite in the world enable to utilize as fuel in different thermal machines, especially in internal combustion engines. A carbon powder containing small molecules about 5–10 micrometers dissolved in water is good fuel for applying in large capacity engines in electrical plants. Aqueous emulsion of coal has possibility of good cooling of injectors cooling and has also good lubricity. The paper gives necessary information about obtaining of water-coal emulsion, its physical properties and technical realization of fuelling system. Initial experimental tests indicate a higher thermal efficiency of engine fuelled by water coal emulsion than engine fuelled by diesel oil and also gas turbine driven by gas from coal gasification technology. The in-creased emission of CO2 can be reduced in the plants simply by chemical reduction. The paper explains thermo-chemical processes taking place in the engines during combustion process. The work parameters results obtained from calculations were compared with those obtained from CI engine fuelled by diesel oil. The paper is a certain challenge for finding a new fuel sources as a competition for crude oil and allows to get acquainted with new engine fuelling technology.

PL

Duże pokłady węgla kamiennego i brunatnego na świecie umożliwiają wykorzystanie jako paliwa w rozlicznych maszynach cieplnych, szczególnie w tłokowych silnikach spalinowych. Sproszkowany węgiel zawierający małe drobiny około 5–10 mikrometrów rozpuszczony w wodzie jest dobrym paliwem do zastosowania w silnikach Diesla o dużej pojemności w elektrowniach. Wodny roztwór węgla umożliwia dobre chłodzenie wtryskiwacza oraz wykazuje również dobrą smarność. Artykuł podaje niezbędne informacje o otrzymywaniu emulsji węglowo-wodnej, podaje jej właściwości fizyczne oraz techniczną realizację takiego systemu zasilania. Wstępne badania doświadczalne wykazały większą sprawność cieplną silników zasilanych taką emulsją niż silniki zasilane olejem napędowym oraz turbin gazowych zasilanych produktami zgazowywania węgla. Większa emisja CO2 może być zredukowana w elektrowniach przez chemiczną redukcję albo sekwestrację. Artykuł wyjaśnia procesy termochemiczne występujące w procesie spalania takich silników. Parametry robocze silnika zasilanego emulsją węglowo-wodną otrzymane z symulacji zostały porównane z parametrami silnika zasilanego olejem napędowym. Artykuł jest próbą znalezienia nowego źródła paliwa jako konkurenta w stosunku do ropy naftowej i pozwala zaznajomić się nową techniką zasilania silnika spalinowego.

4

Ignition of CNG mixtures in spark ignition engines

Mitianiec W.

Journal of KONES

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2012

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Vol. 19, No. 3

297-304

EN

Nowadays in automotive industry, the applying of gaseous fuels and particularly compressed natural gas both in SI and CI engines is more frequent. Application of CNG in the spark ignition internal combustion engines is more real than never before. The paper describes a problem of ignition of CNG mixtures formed in SI engines with direct injection, which requires higher energy supplied by the ignition systems. The main topic of this problem was determined on the basis of the work in NICE project. The paper presents the mathematical model of ignition of CNG mixture and results of calculations. One presents dependencies between different thermal parameters on requiring electric energy. The paper shows also results of experimental results carried out in the caloric chamber done in Cracow University of Technology and chosen results of testing different ignition systems. It was modelled ignition process of the air-methane mixture in the part of combustion chamber with real spark plug. Simulation process was carried out for simple kinetic chemical reaction at initial pressure 20 bar and temperature 900 K. The paper presents calculation CFD model with high density tetrahedral mesh. Transient modelling enables obtaining of the flame spreading in the considered chamber by presenting temperature distribution and kinetic reaction rate for four times. Mass fractions of methane, carbon dioxide and water vapours are shown in dependence on time in the diagrams. The simple combustion model indicated high temperature above 3500 K in the ignition kernel at the beginning of sparking.

5

Study of combustion and pneumatic spark ignition engine

Mitianiec W., Wiatrak W.

Journal of KONES

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2010

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Vol. 17, No. 1

283-290

EN

he paper describes the work of high speed spark ignition engine with additional high pressure air injection during combustion process. The analyzed conception of combustion and pneumatic engine is based on the European patent EPO - EP2 103777 A2 and polish announcement UP RP P-387992. The paper presents the results of theoretical and numerical investigations for different analyzed control parameters of the injection dose of air with comparison of work parameters for standard and modified engine. Additional post air injection enables achieving higher expansion pressure and additional oxygen for better fuel combustion. At proper air dose the charge temperature slightly decreases, which enables applying of a cheaper turbocharger in such engine in regard of thermal resistance of materials. The engine is equipped with electronic control system of air injection and directfuel injection. The paper shows an increase of dynamic engine performance for constant timings and pressure of air injection and variations of engine work in comparison to standard engine. Additionally the paper shows possible energy recovery system of such engine in the car. The conception is a certain input for "downsizing" of engines and reduction of exhaust emission. The results presented in the paper were obtained from computer programs based on prepared mathematical model.

6

Theoretical and experimental study of the ignition process in CNG direct injection SI engines

Mitianiec W., Zioło T., Noga M.

Journal of KONES

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2007

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Vol. 14, No. 3

411-421

EN

The future requirements of CO2 emission decreasing in ICE by applying of new fuels leads also to a design of new engines with direct injection of the compressed natural gas in internal combustion engines with high compression ratio. Because of higher temperature of CNG ignition the SI engines have more effective ignition system than conventional engines. The gas motion, turbulence, charge temperature, spark gap, electrical resistance of the gas and obviously electrical energy of the coil have a big influence on the ignition and burning process in the combustion chamber. The paper includes theoretical and experimental investigations of ignition process in the high charged SI engines with direct CNG injection and in the caloric chamber. The influence of the "tumble" and "swirl" on the sparking is shown by modelling of this process. The paper includes also the thermal efficiency of the ignition process with given values of radiation, conductive and ionization losses. The experimental and mostly simulation tests showed some important factors which influence on the ignition and combustion process of the compressed natural gas. The thermal efficiency of the ignition system increases linearly with the initial pressure in the chamber. The energy consumed by the charge is only a small part of the total energy delivered by the secondary circuit of the coil. The test of the influence of the gas motion on the ignition and combustion process of methane was carried out in CFD environment.

7

Study of stratification of CNG mixture in a high charged SI engine

Mitianiec W.

Journal of KONES

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2006

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Vol. 13, No. 2

323-333

EN

The burning of CNG mixture can occur in very small range of the compression pressure and lean mixture composition. The increased compression pressure requires a big pressure of CNG injection Even for lean mixtures the maximum combustion pressure reaches value near 200 bars. For very lean mixtures and higher compression ratios the misfire occurs, on the other hand for rich mixtures and high compression ratios the detonation is observed. For part load the fuel is injected during the compression stroke, which should form a bigger concentration of fuel near spark plug. The timing of injection should correlate with the piston position BTDC and engine speed in order to enable the adequate stoichiometric mixture near the spark plug during the ignition. The stratification of the charge depends on the location of the injector and the angles of injection nozzles and on the shape of the piston crown. The motion of the injected gaseous fuel required the adequate profile of piston head to turn the fuel stream directly to the spark plug. The flat piston causes that small part of fuel reaches the cylinder cavities and the increase of HC is observed. The paper performs results of calculations of the work engine parameters for 3 types of the piston shapes. The calculations were carried out in the 3-dimensional space with full engine geometry for the same engine speed and injection time. The simulations of CNG injection and combustion process were carried out for motorcycle engine SUZUKI DR-Z400S

8

Optimization of the rich mixture injection system in two-stroke engines

Mitianiec W.

Journal of KONES

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2006

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Vol. 13, No. 3

213-224

EN

Two-stroke engines used in small applications, in order to fulfill the emission requirements, should be equipped with a direct injection system or pneumatic rich mixture injection system. The FAST system in the Piaggio engines is based on the two-throat carburetor. Till now the Piaggio company has not published the physical processes taking place in such engines. The author has carried out the deep study of the process of rich mixture injection by an additional compressor and the results of calculations are presented in the paper. The simulation was done by using of the own computer program based on the mathematical model taking into account the unsteady gas flow of semi-perfect gas, the changed parameters of engine geometry and controlled parameters. The paper includes description of the fuelling system, mathematical model, calculation algorithm, results of calculations for different controlled parameters and comparison with other systems. The FAST computer program enables to define the characteristics of the cylinder charge, engine power, fuel consumption and exhaust gas composition. The simple mechanical fuelling system without electronic participation enables to apply it for the engines driven the small vehicles. However the drive of the compressor by tooth belt from the engine crankshaft decreases the total engine power about 20%.

9

Tankowanie bez elektryczności

Schroeder M.

Analityka : nauka i praktyka

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2006

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nr 3

19-21