• Journal of Korean Port Research
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• v.13 no.2
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• pp.427-436
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• 1999

Simulation model for diffusion of oil spill is developed. The model can perform real time simulation in the case of oil spill accident in the ocean. The model consists of three dimensional ocean circulation model and model for diffusion of oil spill. Real time flow fields which are used in the calculation of advection of oil spill are obtained in the three dimensional ocean circulation model. The model for diffusion of oil spill includes the evaporation dissolution emulsification and downward diffusion. For the verification of the model it is applied to the oil spill from the accident of Sea Prince. The results shows good agreement.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.297-302
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• 2003

This study was carried out to check the contingency planning methods under the analysis of oil spill potential and make a guide line to apply the results to the port of Busan. The expected spilled oil drift patterns are considered with the most probable scenarios under the base of the oil spill potential. The results obtained from this study are as follows: (1) Analysis method of oil spill potent was proposed and the applicability was proved by the application example to the port of Busan to make the contingency plan. (2) Responsible oil spill contingency planning methods / flow are suggested considered environmental factors and the oil spill potential. (3) The coastal waters of Busan was consist of rocky flat, man-made solid shore and beach shore. Marine traffic have high density of oil tanker and cargo ship. Also, oil tanker ship are examined in the small ships to be less than 3000t to supply oil to the ship moored / anchored as well as the large amount of oil tank / basin are located along the coast of Busan port. These systems are introduced to make in put data to the analysis of oil spill potential. (4) According to the analysis of historical records of oil spill accident in Busan, the frequency of accidents by cargo ship rank highest and 45% of accidents is caused by carelessness. about 65% of total accidents shows a small spill accident of less than $10k{\ell}$.

• Journal of Korean Society on Water Environment
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• v.22 no.6
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• pp.1060-1067
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• 2006

Water quality in the Daecheong reservoir has been deteriorated by algal bloom due to nutrient supply from the upstream of the Daecheong reservoir after heavy rainfall. Algal bloom is propagated from eutrophicated tributary into the main body of the reservoir according to the hydrological conditions. This study is aimed to estimate the water current and temperature effect by the simulation of dam spill flow control using water quality model, CE-QUAL-W2 in 2003. Water current was resulted in nutrient transport from upstream of main reservoir and nutrients were delivered up to downstream by fast water velocity. Algal blooms occurred in stagnate zone of reservoir downstream as the current of downstream was retarded according to dam outflow control. Consequently water balance in stagnate zone triggered a rise of water temperature in summer. It affected algal bloom in the embayment of the reservoir. The simulation result by outflow control scenarios showed that spill flow augmentation induced in water body instability of stagnate zone so that water temperature declined. It could be suggested that outflow control minimize algal bloom in the downstream in the flooding season as long as water elevation level is maintained properly.

• Journal of Ocean Engineering and Technology
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• v.25 no.3
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• pp.90-95
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• 2011

On April 20, 2010, a well control event allowed hydrocarbon (oil and gas) to escape from the Macondo well onto Deepwater Horizon (DWH), resulting in an exploration and fire on the rig. While 17 people were injured, 11 others lost their lives. The fire continued for 36 hours until the rig sank. Hydrocarbons continued to flow out from the reservoir through the well bore and blowout preventer (BOP) for 87 days, causing an unprecedented oil spill. Beyond Petroleum (BP) and the US federal government tried various methods to prevent the oil spill and to capture the spilled oil. The corresponding responses were very challenging due to the scale, intensity, and duration of the incident that occurred under extreme conditions in terms of pressure, temperature, and amount of flow. On July 15, a capping stack, which is another BOP on top of the existing BOP, was successfully installed, and the oil spill was stopped. After several tests and subsea responses, the well was permanently sealed by a relief well and a bottom kill on September 19. This paper analyzes the subsea responses and engineering efforts to capture the oil, stop the leaking, and kill the subsea well. During the investigation and analysis of subsea responses, information was collected and data bases were established for future accident prevention and the development of subsea engineering.

• International Journal of Aeronautical and Space Sciences
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• v.16 no.2
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• pp.123-136
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• 2015

The present study numerically investigates the effect of shield on the flow characteristics of Hartmann whistle. The flow characteristics of un-shielded Hartmann whistle are compared with whistles of different shield heights 15 mm, 17 mm, 20 mm, 25 mm and 30 mm. The comparison of Mach number contours and transient velocity vectors of shielded Hartmann whistles with un-shielded ones for the same conditions reveal that the presence of shield causes the exiting jet to stick to the wall of the shield without causing spill-over around the cavity inlet, thus sustaining the shock oscillation as seen in the unshielded Hartmann whistle, which has intense flow/shock oscillation and spill-over around the cavity mouth. The velocity vectors indicate jet regurgitance in shielded whistles showing inflow and outflow phases like un-shielded ones with different regurgitant phases. The sinusoidal variation of mass flow rate at the cavity inlet in un-shielded Hartmann whistle indicates jet regurgitance as the primary operating mode with large flow diversion around the cavity mouth whereas the non-sinusoidal behavior in shielded ones represent that the jet regurgitance is not the dominant operating mode. Thus, this paper sufficiently demonstrates the effect of shield in modifying the flow/shock oscillations in the vicinity of the cavity mouth.

• Journal of Ocean Engineering and Technology
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• v.32 no.6
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• pp.474-484
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• 2018

In this study, a new numerical modeling system was proposed to predict oil spills, which increasingly occur at sea as a result of abnormal weather conditions such as global warming. The hydrodynamic conditions such as the flow velocity needed to calculate oil dispersion were estimated using a three dimensional hydrodynamic model based on the Navier-Stokes equation, which considered all of the physical variations in the vertical direction. This improved the accuracy compared to those estimated by the conventional shallow water equation. The advection-diffusion model for the spilled oil was combined with the hydrodynamic model to predict the movement and fate of the oil. The effects of absorption, weathering, and wind were also considered in the calculation process. The combined model developed in this study was then applied to various test cases to identify the characteristics of oil dispersion over time. It is expected that the developed model will help to establish initial response and disaster prevention plans in the event of a nearshore oil spill.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.2
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• pp.99-110
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• 2016

When a riser is damaged, the oil spills to sea. Oil spills cause huge economic losses as well as a destruction of the marine environment. To reduce losses, it is needed to predict spilled oil volume from risers and the excursion of the oil. The present paper simulated the oil spill for a damaged riser using open source libraries, called Open-FOAM. To verify numerical methods, jet flow and Rayleigh-Taylor instability were simulated. The oil spill was simulated for various damaged leak size, spilled oil volume rates, damaged vertical locations of a riser, and current speeds. From results, the maximum excursion of the spilled oil at the certain time was predicted, and a forecasting model for various parameters was suggested.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.4
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• pp.182-192
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• 2008

In oder to develop a decision supporting system for oil spill response, the prototype of pollution response support system which has integrated oil spill prediction system and pollution risk prediction system has developed for Incheon-Daesan area. Spill prediction system calculates oil spill aspects based on real-time wind data and real-time water flow and the residual volume of spilt oil and spread pattern are calculated considering the characteristic of spilt oil. In this study, real-time data is created from results of real-time meteorological forecasting model(National Institute of Environmental Research) using ftp, real-time tidal currents datasets are built using CHARRY(Current by Harmonic Response to the Reference Yardstick) model and real-time wind-driven currents are calculated applying the correlation function between wind and wind-driven currents. In order to model the feature which is spilt oil spreading according to real-time water flow is weathered, the decrease ratio by oil kinds was used. These real-time data and real-time prediction information have been integrated with ESI(Environmental Sensitivity Index) and response resources and then these are provided using GIS as a whole system to make the response strategy.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.71-71
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• 2018

Sea pollution accidents have been occurred due to the increase of marine ship traffic. Oil spill from the hull hole induced by tanker collision results in the huge sea pollution. Proper and prompt reaction on such oil spill disaster is needed to minimize the damage. Thru-hull emergency wood plug is typically used to manually close small holes, while it is required to develop some mechanical devices for closing large holes in the hull due to huge fluid pressure. Accurate estimation of oil discharge and velocity from such holes are important to develop proper device to control hull hole damage. High resolution CFD modeling investigation on the configurations of hull hole of 7.5 m initial depth and 30 cm diameter, which was observed in the oil spill accident of the Hebei Sprit off the west coast of Korea in 2007, has been carried out to compute the oil spill velocity distribution in terms of flow depth. Friction loss due to the viscous flow and the discharge coefficient of crude oil with specific gravity SG = 0.85 and viscosity of $4-12cP(mPa{\cdot}s)$ at the temperature of $20^{\circ}C-100^{\circ}C$ are presented in terms of Reynolds number based on the results of high-resolution CFD modeling.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.911-918
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• 2013

Two - dimensional numerical analysis model(RMA2), is mainly applied to analyze the flood water levels, velocities and change of river bed at the downstream of Dam. The analysis result be able to influence to Gwangchon bridge from Juam dam, freeboard be insufficient 0.7m to left bank 300m section of dam downstream. Bank overflow is appear to all section of Bosung river to PMF spill condition. Inundated district is appear to river confluence to 200year frequency and is expand to bank overflow to PMF spill condition. Velocity in the channel was simulated high velocity to the bridge and narrow reach and appear to riverbed degradation.