scholarly journals The Role of Magnetic Field Orientation in Vegetable Oil Premixed Combustion

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Dony Perdana ◽  
Lilis Yuliati ◽  
Nurkholis Hamidi ◽  
I. N. G. Wardana
Keyword(s):  
Magnetic Field ◽  
Vegetable Oil ◽  
Laminar Flame ◽  
Burning Velocity ◽  
Stability Limit ◽  
Lewis Number ◽  
Flame Speed ◽  
Premixed Combustion ◽  
Field Orientation ◽  
Magnetic Field Orientation

This study observed the influence of magnetic field orientation on the premixed combustion of vegetable oil. The results show that the magnetic field increased the laminar burning velocity because the spin of electron became more energetic and changes the spin of hydrogen proton from para to ortho. The increase of flame speed became larger on vegetable oil with stronger electric poles. The attraction magnetic field gives the strongest effect against the increase of flame speed and makes flame stability limit wider toward lean equivalence ratio. This is because O2 with the paramagnetic nature is pumped more crossing flame from the south pole (S) to north pole (N) whereas the heat energy carried by H2O from the reaction product with the diamagnetic nature is pumped more crossing flame in the N pole to the S pole. This made the combustion close to Lewis number equal to unity, whereas in the repulsion magnetic poles, S-S, more O2 is pumped into the flame while more heat is pumped out of the flame, and thus, combustion in the flame is leaner and reactions are not optimal. Conversely, at N-N poles, more heat carried by H2O was pumped into the flame while more O2 was pumped out of the flame. As a result, combustion in the flame is richer and the reaction is also not optimal. As a consequence, the velocity of the laminar flame at the repelling poles is lower than that of attracting poles.

scholarly journals The effect of magnetic field variations in a mixture of coconut oil and jatropha on flame stability and characteristics on the premixed combustion

2021 ◽  
pp. 13-22
Author(s):  
Dony Perdana ◽  
Satworo Adiwidodo ◽  
Mochamad Choifin ◽  
Wigo Ardi Winarko
Keyword(s):  
Magnetic Field ◽  
Vegetable Oil ◽  
Laminar Flame ◽  
Coconut Oil ◽  
Flame Speed ◽  
Premixed Combustion ◽  
Flame Stability ◽  
Laminar Flame Speed ◽  
Magnetic Field Variations ◽  
Ratio Range

This study investigates the effect of attracting and repels magnetic fields with the materials of vegetable oil in the form of a mixture of coconut oil and jatropha (B50) against the behavior of stability and characteristics of flame in the process of premixed burning. The fuel for a mixture of vegetable oil of 600 ml was filled into the boiler heated with a gas stove to be evaporated at a temperature of 300 °C and 3 bar pressure was kept constant was mixed with air from the compressor in the burner room. Then a flame was ignited at the end of the nozzle to form a diffusion flame, the flame formed was then given north (N) and south (S). The results showed that the flame speed of the attractive magnetic field was 52.22 cm/sec, the repulsive magnetic field was 50.49 cm/sec while without a magnetic field was 49.79 cm/sec. The increase in the laminar flame speed in the attractive magnetic field is caused by the electron spin becoming more energetic and due to the change in the spin of the hydrogen proton from para to ortho. The attractive magnetic field has the strongest effect on increasing the flame speed. This makes the flame more stable in the equivalency ratio range of 0.75–1.17 compared to without a magnetic field in the same equivalency ratio range. This was so because O2 where it is in nature of paramagnetic was pumped more crossing the flame from south to north poles whereas the heat brought by H2O in nature of diamagnetic was pumped more crossing north to south poles. Whereas on the repel magnetic field, it was hotter when brought by H2O pumped into the flame whereas O2 tended to be pumped going out of the flame. This caused the combustion in the flame was smaller and the reaction was not maximum. As a consequence, the laminar flame speed was more lacking and the reaction was not to the fullest. As a consequence, the laminar flame speed in the repel was fewer than the attract magnetic field

scholarly journals Catalytic Influence of Water Vapor on Lean Blowoff and NOx Reduction for Pressurised Swirling Syngas Flames

2017 ◽  
Author(s):  
Daniel Pugh ◽  
Philip Bowen ◽  
Andrew Crayford ◽  
Richard Marsh ◽  
Jon Runyon ◽  
...  
Keyword(s):  
Elevated Temperature ◽  
Reaction Rate ◽  
Catalytic Effect ◽  
Laminar Flame ◽  
Nox Reduction ◽  
Flame Temperature ◽  
Stability Limit ◽  
Flame Speed ◽  
Laminar Flame Speed ◽  
Water Loading

It has become increasingly cost-effective for the steel industry to invest in the capture of heavily carbonaceous BOF (Basic Oxygen Furnace) or converter gas, and use it to support the intensive energy demands of the integrated facility, or for surplus energy conversion in power plants. As industry strives for greater efficiency via ever more complex technologies, increased attention is being paid to investigate the complex behavior of by-product syngases. Recent studies have described and evidenced the enhancement of fundamental combustion parameters such as laminar flame speed due to the catalytic influence of H2O on heavily carbonaceous syngas mixtures. Direct formation of CO2 from CO is slow due to its high activation energy, and the presence of disassociated radical hydrogen facilitates chain branching species (such as OH), changing the dominant path for oxidation. The observed catalytic effect is non-monotonic, with the reduction in flame temperature eventually prevailing, and overall reaction rate quenched. The potential benefits of changes in water loading are explored in terms of delayed lean blowoff, and primary emission reduction in a premixed turbulent swirling flame, scaled for practical relevance at conditions of elevated temperature (423 K) and pressure (0.1–0.3 MPa). Chemical kinetic models are used initially to characterize the influence that H2O has on the burning characteristics of the fuel blend employed, modelling laminar flame speed and extinction strain rate across an experimental range with H2O vapor fraction increased to eventually diminish the catalytic effect. These modelled predictions are used as a foundation to investigate the experimental flame. OH* chemiluminescence and OH planar laser induced fluorescence (PLIF) are employed as optical diagnostic techniques to analyze changes in heat release structure resulting from the experimental variation in water loading. A comparison is made with a CH4/air flame and changes in lean blow off stability limits are quantified, measuring the incremental increase in air flow and again compared against chemical models. The compound benefit of CO and NOx reduction is quantified also, with production first decreasing due to the thermal effect of H2O addition from a reduction in flame temperature, coupled with the potential for further reduction from the change in lean stability limit. Power law correlations have been derived for change in pressure, and equivalent water loading. Hence, the catalytic effect of H2O on reaction pathways and reaction rate predicted and observed for laminar flames, are compared against the challenging environment of turbulent, swirl-stabilized flames at elevated temperature and pressure, characteristic of piratical systems.

Quantification of cardiac magnetic field orientation during ventricular de- and repolarization

2008 ◽  
Vol 53 (9) ◽  
pp. 2291-2301 ◽  
Author(s):  
Peter Van Leeuwen ◽  
Birgit Hailer ◽  
Silke Lange ◽  
Anita Klein ◽  
Daniel Geue ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Orientation ◽  
Magnetic Field Orientation

A Laminar Burning Velocity Correlation for Hydrogen/Air Mixtures Valid at Spark-Ignition Engine Conditions

2003 ◽  
Author(s):  
Sebastian Verhelst ◽  
Roger Sierens
Keyword(s):  
Chemical Kinetics ◽  
Laminar Flame ◽  
Burning Velocity ◽  
Spark Ignition ◽  
Flame Speed ◽  
Spark Ignition Engine ◽  
Laminar Flame Speed ◽  
Spark Ignition Engines ◽  
Laminar Burning Velocity ◽  
Velocity Correlation

During the development of a quasi-dimensional simulation programme for the combustion of hydrogen in spark-ignition engines, the lack of a suitable laminar flame speed formula for hydrogen/air mixtures became apparent. A literature survey shows that none of the existing correlations covers the entire temperature, pressure and mixture composition range as encountered in spark-ignition engines. Moreover, there is ambiguity concerning the pressure dependence of the laminar burning velocity of hydrogen/air mixtures. Finally, no data exists on the influence of residual gases. This paper looks at several reaction mechanisms found in the literature for the kinetics of hydrogen/oxygen mixtures, after which one is selected that corresponds best with available experimental data. An extensive set of simulations with a one-dimensional chemical kinetics code is performed to calculate the laminar flame speed of hydrogen/air mixtures, in a wide range of mixture compositions and initial pressures and temperatures. The use of a chemical kinetics code permits the calculation of any desired set of conditions and enables the estimation of interactions, e.g. between pressure and temperature effects. Finally, a laminar burning velocity correlation is presented, valid for air-to-fuel equivalence ratios λ between 1 and 3 (fuel-to-air equivalence ratio 0.33 < φ < 1), initial pressures between 1 bar and 16 bar, initial temperatures between 300 K and 800 K and residual gas fractions up to 30 vol%. These conditions are sufficient to cover the entire operating range of hydrogen fuelled spark-ignition engines.

Chiral nematic suspensions of cellulose crystallites; phase separation and magnetic field orientation

1994 ◽  
Vol 16 (1) ◽  
pp. 127-134 ◽  
Author(s):  
Jean-François Revol ◽  
Louis Godbout ◽  
Xue-Min Dong ◽  
Derek G. Gray ◽  
Henri Chanzy ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Phase Separation ◽  
Field Orientation ◽  
Magnetic Field Orientation ◽  
Chiral Nematic
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