• Korean Chemical Engineering Research
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• v.48 no.3
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• pp.375-381
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• 2010

Cetane number of diesel fuel for compression ignition engine is one of main properties for fuel ignition quality. Recently the cetane index has been replaced the cetane number in order to resolve the disadvantage of CFR engine test, but these two value have slightly difference values due to addition of various additives. In this study, we analyzed the cetane number, derived cetane number and cetane index for diesel fuel which was blended with various ratios of biodiesel, kerosene and cetane improver as additives. As a result, Cetane number showed the similar value with derived cetane number, but cetane index showed quite different value with cetane number when biodiesel and cetane improver were used as additives.

• International Journal of Safety
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• v.4 no.2
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• pp.24-29
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• 2005

An experimental study was presented for extinguishing characteristics of liquid fuel fire by water mist($Dv_{0.99}{\leq}200{\mu}m$) containing potassium acetate and sodium acetate trihydrate. To evaluate the extinguishing performance of water mist containing additives, the evaporation characteristics of a water droplet on a heated surface was examined. The evaporation process was recorded by a charge-coupled-device camera. Also, small-scale extinguishing tests were conducted for n-heptane pool fire in ventilated space. During the experiments, flame temperatures were measured, and concentrations of oxygen and carbon monoxide were analyzed by a combustion gas analyzer. The average evaporation rate of water droplet containing additives was lower than that of pure water at a given surface temperature and decreased with the concentration increase due to the precipitation of salt in the liquid-film and change of surface tension. In case of using additives, the fire extinguishing times was shorter than that of pure water at a given discharge pressure and it was because the momentum of a water droplet containing additives was increased. And also dissociated metal atoms, potassium or sodium, were reacted as a scavenger of the major radical species OH, H which were generated for combustion process. Moreover, at a high pressure of 4 MPa, the fire was extinguished through blowing effect as well as primary extinguishing mechanisms.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.957-967
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• 2017

Firing test of the fuel grain for solid fuel ramjet with additives and ignition support material was conducted. Fuel grain consist of HTPB mixed with AP particle 15 wt.%, Boron particle 5 wt.%. To cause the short ignition delay, ignition support consist of $NC/BKNO_3$ and composite propellant was coated to the fuel grain. An oxidant gas having a controlled temperature, pressure and oxygen composition close to the air condition in the ramjet combustor was supplied using the Ethanol blended $H_2O_2$ gas generator. Gas was set to flow at a mass flow rate of 150 g/s and mass flux of $200kg/m^2s$ in the grain port. Through the test, ignition support operated well and ignition delay of 0.5. During the test, stable chamber pressure with 8 bar and high combustion efficiency of 0.86 was confirmed.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.178.1-178.1
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• 2011

DME is generally expected to be used as a promising clean alternative fuel to diesel fuel. DME is not natural product but a synthetic product that is produced either through the dehydration of methanol or a direct synthetic from syngas. As DME has no carbon-carbon bond in its molecular structure and is an oxygenate fuel, it's combustion essentially generates no soot. DME has such cetane number of 55~60 that it can be used as a diesel engine fuel. However, DME has low lubricity but a proven method to solve the poor lubricity is by adding lubricity improver. Therefore, the aim of this study is to develop lubricity improver of DME as a transport fuel in Korea. In this study, we investigated a possibility of fatty acid ester compounds as a candidate to improve DME lubricity as compared with current lubricity improver of diesel. We also evaluated quality characteristics, storage stability of DME with lubricity additives.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.2
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• pp.49-56
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• 2006

The single droplet combustion characteristics of multicomponent fuel such as diesel-oxygenate and diesel-paraffin blends under high ambient temperature and atmospheric pressure were investigated in the study. The results of the study may be concluded as follows : In the combustion of diesel fuel droplet with additive of oxygenate and paraffin, the dimensionless droplet size of $(D/D_o)^2$ was linearly decreased with time. A fuel droplet with low boiling temperature additives and in high boiling temperature diesel fuel evaporates and burns faster than usual diesel fuel. This rapid burning may result from so-called "micro-explosion" and its burning intensity varies with the types of additives. The results above may suggest that rapid evaporation of oxygenate additive in the middle stage of combustion can contribute much to combustion improvement of blended fuels. When compared to ordinary diesel fuel, neat oxygenate and paraffin fuels show blue flame during entire combustion which prove smokeless combustion.

• Tribology and Lubricants
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• v.16 no.5
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• pp.332-340
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• 2000

The reduction of sulfur content in the diesel fuel has caused the poor lubricity of diesel fuel in the distributor type injection pumps of diesel engines that use the diesel for lubrication of their moving parts. To investigate the reason for poor lubricity of low sulfur diesel fuels, the wear scar diameters by HFRR (High Frequency Reciprocating Rig) were measured on the diesel fuels from Korean markets and the results were compared with their physical and chemical properties. Also, the lubricity change and the improvement effects on lubricity additives for the ultra low sulfur diesel fuel, were made experimentally, that will be regulated to a maximum of 0.005 wt% from about 2005 were evaluated. As a result, a good correlation was found between the wear scar diameter and the polyaromatic compound which includes heterocyclic compound in the diesel fuel. It was also found that the content of polyaromatic compound including heterocyclic compound was affected by the amount of desulfurization treatment fraction. And the lubricity additives with ester base were more effective than that with acid base on the ultra low sulfur diesel fuel. Therefore, it is suggested that the factors affecting the lubricity stated above should be taken into account to improve the lubricity property of the diesel fuel in the refining process.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.163-166
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• 2009

For the preparation of Aluminum-slurry fuel, the effects of process parameters on the aluminum dispersion stability in the liquid fuel have been investigated. The dispersion stability of aluminum-slurry fuels could be monitored by measurements through Turbiscan using the scattering of the Laser. Through the application of various additives, TPAB (Tetrapropyl ammonium bromide) showed more reasonable performance than others.

• Journal of the korean Society of Automotive Engineers
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• v.3 no.2
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• pp.18-26
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• 1981

The purpose of this paper is to study the possibility of practical use of gasoline-methanol mixed fuel as an alternative fuel of gasoline engines in the light of engine performances and harmful exhaust emissions as well as mixings and separations of the mixed fuels. When the methanol of 99.8% purity is mixed with super or regular gasoline available on the market today, the experimental results obtained without modifying carburetor in this study are as follows; 1.The separation ratio depends upon the gasoline-methanol mixing ratio only, regardless of fuel temperature and fuel additives for preventing separation of phase. 2.The critical absorption ratio is affected by the gasoline-methanol mixing ratio, its temperature and the quantity of fuel additives. 3.Concerning the distillation temperature, the initial point of all sorts of fuels is almost same,but 10% point and 35-60% point of mixed fuels are lower than those of gasoline only. 4.In case of throttle valve opening set, engine output using the mixed fuels is decreased compared to gasoline, but thermal efficiency is increased as a consequence of decreasing specific energy consumption. 5.In case of fixed load test, thermal efficiency is increased at low engine speed even under low part-load as well as under comparatively high part-load including full load. 6.CO and NOx emissions are reduced remarkably with the mixed fuels.

• International Journal of Automotive Technology
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• v.3 no.1
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• pp.1-8
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• 2002

There is Increasing world-wide interest in diesel particulate filters (DPF) because of their proven effectiveness in reducing exhaust smoke and particulate emissions. Fine particulates have been linked to human health . DPF use requires a means to secure the bum-out of the accumulated soot, a process called regeneration. If this is not achieved, the engine cannot continue to operate. A number of techniques are available, but most are complex, expensive or have a high electrical demand. The use of fuel additives to catalyse soot bum-out potentially solves the problem of securing regeneration reliably and at low cost. Work on organo-metallic fuel additives has shown that certain metals combine to glove exceptional regeneration performance. Best performance was achieved with a combination of iron and strontium based compounds. Tests were carried out un a bed engine and on road vehicles, which demonstrated effective and reliable regeneration from a tow dose fuel additive, using a single passive DPF. No control valves, flow diverters. heaters or other devices were employed to assist regeneration. Independent particle size measurements showed that there were no harmful side effects from the use of the iron-strontium fuel additive.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.27-33
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• 2014

The significance of soil environment is gradually increased due to the soil and underwater contamination caused by petroleum leak accidents. It requires a high cost and long period for the purification of soil compared with other environmental matrix such as water and air. For this reason, it has been embroiled in a legal conflict to find the pollution source and charge of cleanup. In this study, we analyzed the physical properties and typical additives of jet fuel to search a method that can distinguish kerosene and jet fuel contamination. In particular, the chemical marker in kerosene was visualized by the developer and the additives in jet fuel, such as antioxidant and metal deactivator were detected by GC-MS. This study could be used to judge petroleum source at soil contaminant accident sites.