• Journal of the Korean Society for Marine Environment & Energy
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• v.1 no.2
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• pp.40-51
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• 1998

The interaction of contained oil slicks with current was investigated with a two-dimensional experimental setup in the circulating water channel facility. A vertical plate was used to contain the oils against the currents and the evolution of the oil slick, mainly focusing on the water/oil interface, was examined with an aid of a laser sheet. Two different oils - soy bean oil and diesel oil - were studied with varying the current speed (10 cm/sec to 35 cm/sec), the barrier depth (4 cm and 8 cm) and the volume of oil (2 liter to 12 liter). Different types of the interface behavior were observed according to the conditions and their mechanism was discussed based basically on the dimensional analysis. The critical speeds of two types of oil loss mechanism (entrainment failure and drainage failure) were also examined.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.6
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• pp.589-598
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• 2000

The vapor-liquid equilibrium and miscibility measurement apparatus was developed and used to obtain data for refrigerant/oil mixture. The vapor-liquid equilibrium and miscibility data for R-410a/POE32 and R-410A/POE46 oil mixtures are obtained over the temperature range from -20 to $60^{\circ}C\;with\;10^{\circ}C$ intervals and the oil concentration range from 0 to 90 wt%. Using the experimental data, an empirical model is developed to predict the temperature-pressure-concentration relations for R-410A/POE oil mixtures at equilibrium. In the R-410A/POE32 oil mixture, the average root-mean-square deviation between measured data and calculated results from the empirical model is 2.00% and in the R-410a/POE46 oil mixture, that is 3.69%. Flory-Huggins theory is also used to predict refrigerant/oil mixture behavior. Miscibility for R-410A/POE32 oil mixture was observed all over the experimental conditions. Immiscibility for R-410A/POE46 oil mixture was observed at the low oil concentrations(10~30 wt%).

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.3
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• pp.320-330
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• 1999

A numerical study was performed to investigate spray behavior and its interaction with air flow in a flame holding region of an oil burner(0.1MW) using the KIVA3 code. The numerical results in shape of the recirculating flow and size of the recirculation zone under different conditions were compared to those experimental results. The numerical results in fuel droplet trajectory show that a droplet under 30${\mu}m$ can follow the air flow but a droplet over 50${\mu}m$ penetrates the recirculation zone due to large momentum and a droplet of 30-50${\mu}m$ can follow the recirculating flow or pene-trates the recirculation zone.

• Transactions of Materials Processing
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• v.19 no.4
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• pp.236-241
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• 2010

The frictional behavior of bare steel sheet highly depends on surface roughness. It was investigated that the change of surface roughness of bare steel sheet due to deformation for each forming mode. The flat type friction test was done to check the effect of surface roughness change on frictional characteristics of bare steel sheet. As increasing the deformation, the Ra value was increased at stretching forming mode and drawing forming mode, however the change of Pc showed different trends. The Pc was decreased as increasing stretch deformation but increased at compression deformation. At drawing forming mode, the friction coefficient was increased as deformation was increased after initial big drop with drawing oil. As deformation was increased, the friction coefficient was decreased with drawing oil at stretching forming mode. The results show that the deformation changes the surface roughness and frictional characteristics of steel sheet but the effect depends on the forming mode.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.3
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• pp.193-204
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• 2011

To develop more robust oil boom which is vulnerable to various failure mode under severe weather condition, highly accurate wave model is developed using Spatially filtered Navier-Stokes Eq., LDS (Lagrangian Dynamic Smagorinsky model) for residual stresses, SPH (Smoothed Particle Hydrodynamics). To clarify the hydraulic characteristics of floating type oil boom, we numerically simulate the behavior of oil spill around oil boom under very energetic progressive waves. At the first stage, we firmly anchored the oil boom, and then, allowed the excursion of the oil boom. It turns out that oil boom with skirt of enough length (longer than 30% of depth) effectively confines the oil spill even against very energetic waves. We can also observe obliquely descending vertical eddies between y = 1~2 m as horizontal vortices shedding at the interface of oil spill and water are diffused toward the bottom, which is believed to be the birth, growing and break-down of Kelvin-Helmholz wave.

• Journal of Nutrition and Health
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• v.28 no.7
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• pp.602-611
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• 1995

This study was designed to find out the effects of $\omega$-3 and $\omega$-6 polyunsaturated and saturated fatty acid from prenatal to growing period on the brain growth and behavioral development of rats. Rats(Sprague-Dawley strain) were fed experimental diets-fish oil, corn oil or beef tallow-with different contents of $\omega$-3 and $\omega$-6 fatty acids throughout the prenatal and lactational period and up to 10 weeks of age. DNA and RNA concentration of rat brain were determined at 0, 3, 6 weeks of age and choline and acetylcholine concentrations were analyzed at 10 weeks of age. When the rats were 7 weeks of age, position reversional test in a Y-shaped water maze for 4 weeks was measured. The experimental results obtained are summarized as follows. Food intakes were significantly lower in fish oil group and body weight gain was low in the group fed beef tallow and the groups fed fish oil and corn oil were somewhat good. Food efficiency ratio was not significantly different among the groups. Brain weight was not affected by the fatty acid composition of experimental diets and DNA and RNA concentration of the rat brain were consistently maintained at the same level. It was not different significantly among the dietary groups in the DNA and RNA concentrations of the rat brain during the experimental period. The acetylcholine concentration in the fish oil group was somewhat higher than the other groups. The position reversional test in a Y-shaped water maze showed a significant difference the score of test among the experimental groups. The score of the rats fed the fish oil diet was significantly higher than the other groups and the concentration of acetylcholine in brain were too. Therefore the correlatin between the Y-shaped water maze test score and the acetylcholine concentratin in the brain was found. Above finding support the content that dietary fatty acid composition does not affect to the brain cell number and cell size but the behavior development is influenced. Therefore, the improvement of behavior development is required the effective usage of finny tribe.

• The Journal of Engineering Geology
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• v.25 no.4
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• pp.577-585
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• 2015

Contamination of soil due to an oil spill influences its subsequent behavior. An investigation was conducted to study the effect of oil viscosity on compaction characteristics, coefficient of permeability, and shear strength. Water permeability was also determined by using Kerosene, Engine oil, and Crude-oil as contaminants. The test results indicate that the compaction characteristics are influenced by oil contamination. Direct shear test was conducted to investigate the effect of oil in the pore space in sandy ground. angle of internal friction of sand (based on total stress condition) decreases due to presence of oil within the pore spaces in sand.

• Advances in nano research
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• v.15 no.6
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• pp.541-550
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• 2023

The escalating growth of industrial sectors has led to a pervasive global problem—oil pollution, particularly in industrial areas. The release of substantial volumes of oil and its by-products into the environment has resulted in extensive contamination. Multiple factors contribute to the entry of these substances into water bodies and soils, thereby inflicting irreparable consequences on ecosystems, natural resources, and human health. Consequently, it becomes imperative to comprehend the characteristics and behavior of oil pollution, anticipate its impacts, and develop effective mitigation strategies. Understanding this intricate issue requires considering the physicochemical properties of the environment, the interactions between oil and sediments, and biological factors such as evaporation and dissolution. Although the oil industry has brought about remarkable advancements, its activities have raised significant concerns regarding pollution from extraction and production processes. Oil-rich nations face a particularly challenging predicament of soil pollution caused by petroleum compounds. The areas surrounding oil exploration mines and refineries often endure contamination due to oil leakages from storage tanks and transmission lines resulting from deterioration and damage. Investigating the dispersion of such pollutants and devising methods to remediate petroleum-contaminated soil represent crucial and intricate issues within the realm of environmental geotechnics.

• International Journal of Fluid Machinery and Systems
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• v.6 no.1
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• pp.1-10
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• 2013

Jet pump is one type of artificial lifts and is used when depth and deviation of producing wells increases and pressure depletion occurs. In the present study, numerical analysis has been carried out to analyze the flow behavior and find the performance of the jet pump. Reynolds-averaged Navier Stokes equations were solved and k-${\varepsilon}$ turbulence model was used for simulations. Water and light oil as primary fluids were used to pump water, light oil and heavy oil. The ratios of area and length to diameter of the mixing tube were considered as design parameters. The pump efficiency was considered to maximize for the downhole conditions. It was found that the increase in viscosity and density of the secondary fluid reduced efficiency of the system. Water as primary fluid produced better efficiency than the light oil. It was also found that the longer throat length increased efficiency upto 40% if light oil was used as primary fluid and secondary fluid viscosity was 350 cSt.

• Proceedings of the SAREK Conference
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• 2004.11a
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• pp.147-147
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• 2004