Thermodynamic Analysis of Evaporation Characteristics of Moving Two-Component Liquid Fuel Droplets in Pre-Vaporizer Systems

2012 ◽  
Author(s):  
S. Raghuram ◽  
Vasudevan Raghavan
Keyword(s):  
Atmospheric Pressure ◽  
Liquid Fuel ◽  
Droplet Diameter ◽  
Liquid Fuels ◽  
Liquid Equilibrium ◽  
Fuel Component ◽  
Fuel Droplets ◽  
Nusselt Numbers ◽  
Two Component ◽  
Methyl Butyrate

In the current study, a thermodynamic model is presented for predicting the vaporization characteristics of moving two-component fuel droplets, at an ambient temperature of 350 K, atmospheric pressure and with an initial droplet diameter of 100 microns, as typically observed in a gas turbine pre-vaporizing system. Liquid fuels considered are iso-octane (surrogate of gasoline) and decane (surrogate of diesel), blended with ethanol and methyl-butyrate (surrogate of biodiesel), respectively. The model evaluates the vapor-liquid equilibrium based on activity coefficients calculated using UNIFAC group contribution method. The gas-phase properties are calculated as functions of temperature and mixture molecular weight. The temporally varying parameters such as equilibrium surface temperature, concentration of the higher volatile fuel component, evaporation constant and droplet Reynolds and Nusselt numbers have been studied. Variation of integrated parameters such as time-average evaporation constant, droplet lifetime, average velocity and the final droplet penetration distance are also discussed.

scholarly journals Thermodynamic Analysis of Evaporation of Levitated Binary and Ternary Liquid Fuel Droplets under Normal Gravity

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
S. Raghuram ◽  
Vasudevan Raghavan
Keyword(s):  
Gas Phase ◽  
Atmospheric Pressure ◽  
Liquid Fuel ◽  
Normal Gravity ◽  
Hydrocarbon Fuel ◽  
Droplet Surface ◽  
Liquid Equilibrium ◽  
Fuel Droplets ◽  
Ternary Fuel ◽  
Fuel Components

The present study presents a thermodynamic model for predicting the vaporization characteristics of binary and ternary hydrocarbon fuel droplets under atmospheric pressure and normal gravity conditions. The model employs activity coefficients based on UNIFAC group contribution method and evaluates the vapor-liquid equilibrium of binary and ternary droplets. The gas-phase properties have been evaluated as a function of temperature and mixture molecular weight. The model has been validated against the experimental data available in literature. The validated model is used to predict the vaporization characteristics of binary and ternary fuel droplets at atmospheric pressure under normal gravity. Results show multiple slopes in the droplet surface regression indicating preferential vaporization of fuel components based on their boiling point and volatility. The average evaporation rate is dictated by the ambient temperature and also by composition of the mixture.

scholarly journals Is the Fischer-Tropsch Conversion of Biogas-Derived Syngas to Liquid Fuels Feasible at Atmospheric Pressure?

Energies ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 1031 ◽  
Author(s):  
Rawan Hakawati ◽  
Beatrice Smyth ◽  
Helen Daly ◽  
Geoffrey McCullough ◽  
David Rooney
Keyword(s):  
Atmospheric Pressure ◽  
Active Sites ◽  
Liquid Fuel ◽  
Biogas Production ◽  
Liquid Fuels ◽  
Feed Ratio ◽  
Small Scale ◽  
Fischer Tropsch ◽  
Technical Problems ◽  
The Eu

Biogas resulting from anaerobic digestion can be utilized for the production of liquid fuels via reforming to syngas followed by the Fischer-Tropsch reaction. Renewable liquid fuels are highly desirable due to their potential for use in existing infrastructure, but current Fischer-Tropsch processes, which require operating pressures of 2–4 MPa (20–40 bar), are unsuitable for the relatively small scale of typical biogas production facilities in the EU, which are agriculture-based. This paper investigates the feasibility of producing liquid fuels from biogas-derived syngas at atmospheric pressure, with a focus on the system’s response to various interruption factors, such as total loss of feed gas, variations to feed ratio, and technical problems in the furnace. Results of laboratory testing showed that the liquid fuel selectivity could reach 60% under the studied conditions of 488 K (215 °C), H2/CO = 2 and 0.1 MPa (1 bar) over a commercial Fischer–Tropsch catalyst. Analysis indicated that the catalyst had two active sites for propagation, one site for the generation of methane and another for the production of liquid fuels and wax products. However, although the production of liquid fuels was verified at atmospheric pressure with high liquid fuel selectivity, the control of such a system to maintain activity is crucial. From an economic perspective, the system would require subsidies to achieve financial viability.

scholarly journals Numerical Study of Evaporation Modelling for Different Fuels at High Operating Conditions in a Diesel Engine

2021 ◽  
Vol 12 (1) ◽  
pp. 8
Author(s):  
Ali Raza ◽  
Sajjad Miran ◽  
Tayyab Ul Islam ◽  
Kishwat IJaz Malik ◽  
Zunaira-Tu-Zehra ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Liquid Fuel ◽  
Fuel Injection ◽  
Numerical Study ◽  
Droplet Diameter ◽  
Operating Conditions ◽  
Injection System ◽  
Diesel Fuels ◽  
Fuel Droplets ◽  
Engine Cylinder

A fuel injection system in a diesel engine has different processes that affect the complete burning of the fuel in the combustion chamber. These include the primary and secondary breakups of liquid fuel droplets and evaporation. In the present paper, evaporation of two different diesel fuels has been modelled numerically. Evaporation of n-heptane and n-decane is governed by the conservation equations of mass, energy, momentum, and species transport. Results have been plotted by varying the droplet diameter and temperature. It was observed that droplet size, temperature of droplets, and ambient temperature have notable effect on the evaporation time of diesel fuel droplets in the engine cylinder.

NONEQUILIBRIUM DIFFUSION COMBUSTION OF LIQUID FUEL DROPLETS AND SPRAYS MODELING

2012 ◽  
Vol 43 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Nickolay N. Smirnov ◽  
V. F. Nikitin ◽  
V. V. Tyurenkova
Keyword(s):  
Liquid Fuel ◽  
Diffusion Combustion ◽  
Fuel Droplets

Vapour-liquid equilibrium in the isobutyl formate-isobutyl alcohol and n-butyl formate-isobutyl alcohol systems at atmospheric pressure

1979 ◽  
Vol 44 (12) ◽  
pp. 3501-3508 ◽  
Author(s):  
Jan Linek
Keyword(s):  
Experimental Data ◽  
Fourth Order ◽  
Atmospheric Pressure ◽  
Isobutyl Alcohol ◽  
Liquid Equilibrium ◽  
The Third

Isobaric vapour-liquid equilibria in the isobutyl formate-isobutyl alcohol and n-butyl formate-isobutyl alcohol systems have been measured at atmospheric pressure. A modified circulation still of the Gillespie type has been used for the measurements. The experimental data have been correlated by means of the third- and fourth-order Margules equations.

Liquid-liquid equilibrium in binary glycols-toluene and glycols-xylene systems

1982 ◽  
Vol 47 (6) ◽  
pp. 1686-1694 ◽  
Author(s):  
Lumír Mandík ◽  
František Lešek
Keyword(s):  
Atmospheric Pressure ◽  
Binary Systems ◽  
Liquid Equilibrium ◽  
Benzene Toluene

Liquid-liquid equilibria were determined in the following binary systems: 1,2-ethandiol/toluene, 1,2-ethandiol/xylene, 1,2-propandiol/toluene, 1,2-propandiol/xylene, 1,4-butandiol/toluene, 1,4-butandiol/xylene, 1,3-butandiol/toluene, 1,3-butandiol/xylene, 1,3-butandiol/p-xylene, 2,2'-dioxydiethanol/toluene, 2,2'-dioxydiethanol/xylene. The solubility of 2,2-dimethyl-1,3-propandiol in benzene, toluene and xylene was also measured. Critical solubility temperatures at atmospheric pressure were determined for systems containing 1,2-propandiol and 1,3-butandiol.

scholarly journals Interactive Effects in Two-Droplets Combustion of RP-3 Kerosene under Sub-Atmospheric Pressure

Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1229
Author(s):  
Hongtao Zhang ◽  
Zhihua Wang ◽  
Yong He ◽  
Jie Huang ◽  
Kefa Cen
Keyword(s):  
Burning Rate ◽  
Atmospheric Pressure ◽  
High Speed ◽  
Ambient Pressure ◽  
Interactive Effects ◽  
Propagation Time ◽  
High Speed Camera ◽  
Single Droplet ◽  
Fuel Droplets ◽  
Spacing Distance

To improve our understanding of the interactive effects in combustion of binary multicomponent fuel droplets at sub-atmospheric pressure, combustion experiments were conducted on two fibre-supported RP-3 kerosene droplets at pressures from 0.2 to 1.0 bar. The burning life of the interactive droplets was recorded by a high-speed camera and a mirrorless camera. The results showed that the flame propagation time from burning droplet to unburned droplet was proportional to the normalised spacing distance between droplets and the ambient pressure. Meanwhile, the maximum normalised spacing distance from which the left droplet can be ignited has been investigated under different ambient pressure. The burning rate was evaluated and found to have the same trend as the single droplet combustion, which decreased with the reduction in the pressure. For every experiment, the interactive coefficient was less than one owing to the oxygen competition, except for the experiment at L/D0 = 2.5 and P = 1.0 bar. During the interactive combustion, puffing and microexplosion were found to have a significant impact on secondary atomization, ignition and extinction.

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