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Investigation of glycerol doping on ignition delay times and laminar burning velocities of gasoline and diesel fuel

Jach A., Cieślak I., Teodorczyk A.

Combustion Engines

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2017

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R. 56, nr 2

167--175

EN

Glycerol is a major by-product of biodiesel production. Per one tone of produced biodiesel, one hundred kilograms of glycerol is produced. Production of glycerol is increasing due to increase of demand for biodiesel. One of methods of glycerol utilization is combustion. Recent experimental studies with use of a diesel engine and a constant volume combustion chamber show that utilization of glycerol as a fuel results in lower NOx emissions in exhaust gases. It combusts slower than light fuel oil, what is explained by higher viscosity and density of glycerol. Glycerol has low cetane number, so to make combustion in a diesel engine possible at least one of the following conditions need to be fulfilled: a pilot injection, high temperature or high compression ratio. The aim of the paper is to compare glycerol to diesel and to assess influence of glycerol doping on gasoline and diesel fuel in dependence of pressure, temperature and equivalence ratio. The subject of this study is analysis of basic properties of flammable mixtures, such as ignition delay times and laminar burning velocities of primary reference fuels (diesel: n-heptane and gasoline: iso-octane). Calculations are performed with use of Cantera tool in Matlab and Python environments. Analyses of influence of glycerol on ignition delay times of n-heptane/air and iso-octane/air mixtures covered wide range of conditions: temperatures from 600 to 1600 K, pressure 10-200 bar, equivalence ratio 0.3 to 14, molar fraction of glycerol in fuel 0-1 in air. Simulations of LBV in air cover temperatures: 300 K and 500 K, pressures: 10, 40, 100, 200 bar and equivalence ratio from 0.3 to 1.9. Physicochemical properties of gasoline, diesel and glycerol are compared.

2

Numerical analysis of detonation propensity of hydrogen-air mixtures with addition of methane, ethane or propane

Jach A., Teodorczyk A.

Archivum Combustionis

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2016

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Vol. 36 nr 1

47--58

EN

The detonation propensity of hydrogen-air mixtures with addition of methane, ethane or propane in wide range of compositions is analyzed. The analysis concerned the detonation cell width, ignition delay time, RSB and χ parameters. Results are presented as a function of hydrogen molar fraction. Computations were performed with the use of three Cantera 2.1.1. scripts in the Matlab R2010b environment. The validated mechanisms of chemical reactions based on data available in the literature were used. Six mechanisms were assessed: GRI-Mech 3.0, LLNL, SanDiego, Wang, POLIMI and AramcoMech. In conclusion, the relation between detonation propensity parameters is discussed.

3

Analysis of combustion process in industrial gas engines powered with high methane and nitrified low-calorific gases

Rojewski J., Ślefarski R., Wawrzyniak J.

Silniki Spalinowe

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2013

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R. 52, nr 1

42-50

EN

The paper presents the results of an investigation of gas engines used in the Polish system of natural gas transmission. The investigation concerned both four-stroke and two-stroke engines. The engines were fed with two kinds of gas fuel - low-calorific natural gas containing 54.5 % of methane, and with high-methane (up to 95 %) natural gas. Combustion in both types of engines with different methods of mixture supply into the cylinder was analysed for different parameters. The paper also presents numerical computations of basic physical values characterizing combustion of gas fuels in engines. The computations were made with Cantera numerical code based on the mechanism of elementary reactions occurring while burning methane GRI 3.0 for various molar fractions of methane in the gas fuel.

PL

W artykule przedstawiono rezultaty badań silników gazowych wykorzystywanych w polskim systemie przesyłowym gazu ziemnego. Badania te wykonano na silnikach cztero- i dwusuwowych. Jednostki te były zasilane dwoma rodzajami paliw gazowych: niskokalorycznym gazem ziemnym o zawartości metanu wynoszącej 54,5 % oraz wysokometanowym gazem ziemnym zawierającym do 95 % metanu. Analizie poddano proces spalania w wyżej wymienionych silnikach dla różnych parametrów eksploatacyjnych oraz różnych metod doprowadzenia mieszanki do cylindra. Przedstawiono również obliczenia numeryczne podstawowych wielkości fizycznych charakteryzujących proces spalania paliw gazowych w silnikach. Obliczenia przeprowadzono przy użyciu kodu numerycznego Cantera, bazującego na mechanizmie reakcji elementarnych zachodzących przy spalaniu metanu GRI 3.0 dla różnych udziałów molowych metanu w gazie paliwowym.

4

Modelowanie reaktora CPOX dla systemu wysokotemperaturowego ogniwa paliw

Miklis T.

Pomiary Automatyka Robotyka

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2012

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R. 16, nr 2

62-64

PL

Reaktory CPOX pozwalają na stosowanie obecnie dostępnych paliw (gaz naturalny, diesel, dodekan) do napędzania wysokotemperaturowych ogniw paliwowych. Celem badań było stworzenie miarodajnego i szybkiego modelu takiego reaktora. Do obliczeń równowagi reakcji chemicznych zastosowano toolbox Cantera w środowisku MATLAB. Przeprowadzone symulacje wyznaczyły opty-malną koncentrację powietrza i paliwa doprowadzanego do reaktora. Odpowiednio dobrane parametry pozwoliły na maksymalizację wytwarzanego wodoru, który wykorzystywany jest do napędzania ogniwa paliwowego.

EN

CPOX reactors allow the usage of currently available fuels (natural gas, diesel, dodecane) to power solid oxide fuel cells. The aim of this research was to develop a reliable and fast model of such reactor. MATLAB’s Cantera toolbox was used for the chemical equilibrium calculations. The simulations set the optimum concentration of air and fuel supplied to the reactor. Properly selected parameters maximized the hydrogen yield used to power the fuel cell.