연안해역 유류분산의 수치모델링

류청로,장선덕,이화운 ( Cheong Ro Ryu,Sun Duck Chang,Hwa Woon Lee ) 한국물환경학회 1993 한국물환경학회지 Vol.9 No.3

The aim of this study is to give an overview of existing oil spill models that deal with the physical, chemical and biological aspects of fate/behavior of spilled oil, and to develop a feasible, sophisticated, design purpose model of oil spill in the coastal waters. The processes of oil weathering and movements are reviewed in detail, and the characteristics of existing oil spill fate and behavior models are examined and classified, so that an ideal model may be defined. After the evaluation of the existing models, a new model which can be practically applied to the coastal waters are developed considering meteorological and hydraulic factors in the coastal waters including advection and weathering mechanisms summarized in the review work. The wind field effect including land-sea breezes near the coastal area are considered by the comprehensive 3-D meteorological model. The oil-holding capacity and removal coefficient as well as the wave and current dynamics near the coast are included. Other parameters which may affect the advection and weathering of spilled oil are considered as same as in the typical conventional oil spill models. The applicability and feasibility of the model are discussed by comparative applications of the typical conventional model and the developed model to the South-East Coastal Waters of Korea.

A New Design Method of Rubble Mound Structures with Stability and Wave Control Consideration

류청로,Ryu, Cheong Ro Korean Society of Civil Engeneers 1987 대한토목학회논문집 Vol.7 No.3

구조물(構造物)의 안정성(安定性)과 파랑제어기능(波浪制御機能)을 고려(考慮)한 새로운 사석구조물(捨石構造物) 설계법(設計法)을 제안(提案)하였다. 이 설계법(設計法)은 임의의 파랑조건하(波浪條件下)에서 파랑(波浪)의 반사(反射) 및 run-up을 저감(低減)시키고, 안정성(安定性)을 증대(增大)시키는 설계개념(設計槪念)을 가졌다. 설계식(設計式)은 허용파괴율(許容破壞率)과 안정성(安定性)에 대한 파군특성(波群特性)의 영향(影響) 도입(導入)하여 유도하였으며, 이에는 해안파(海岸波)의 평균(平均) run-sum이라는 새로운 외력개념(外力槪念)이 사용(使用)되었다. 마지막으로 이 새로운 설계법(設計法)에 의한 일양단면(一樣斷面)과 복합단면(複合斷面) 사석구조물(捨石構造物) 설계예(設計例)로부터 이 설계법(設計法)의 유용성(有用性)과 이점(利點)을 검증(檢證)하였다. A new design method of rubble mound structures that includes the considerations of stability and wave control is proposed. Using the method, design of structures that reduce the wave reflection and run-up and increase the rubble stability is assured under the given wave conditions. The new design formula is developed so that the allowable prcentage of damage and the wave grouping effects on rubble stability are also considered in design. For this a new definition of the mean run-sum is made. Finally, the new method is applied for the design of uniform and composite slope rubble mound structures and the significant advantages are found.

부산 송도해수욕장과 해안공학의 뉴 패러다임

류청로,Ryu, Cheong-Ro 한국해안해양공학회 2013 해안과 해양 Vol.6 No.2

생태계 제어 시설물의 설계 및 배치 최적화(2) -흐름장에서의 인공어초의 침하 및 매몰 특성-

류청로,김현주,이한수,신동일,RYU Cheong-RO,KIM Hyeon-Ju,LEE Han-Su,SHIN Dong-Il 한국수산과학회 1997 한국수산과학회지 Vol.30 No.1

Sediment transport around artificial habitat which is induced by the change ol flow due to installation of the structure plays a role not only as a defect function of subsidence and burial but also bottom-environment control function. This study examined the characteristics of local scouring and deposition with sediment sizes, current velocities and installation direction of artificial habitat in flow field. Resultant subsidence and burial processes are investigated and discussed with Reynolds number. Together with sediment number and dimensionless time elapse, prediction formulas are established by combining these relationships. Bottom control function as cultivating effects is discussed with installation direction, and applicability of countermeasures is compared and stone pavement method is recommended.

사석구조물(捨石構造物)의 안정성(安定性)에 관한 수리모형(水理模型)의 축척효과(縮尺?果)

류청로,Ryu, Cheong Ro 대한토목학회 1987 대한토목학회논문집 Vol.7 No.3

Scale effects of stability, run-up, run-down and reflection of layered coastal structures are investigated through the experiments with 7 kinds of hydraulic scale models. The occurrence mechanism and the control method of scale effects are also discussed. As a result, it is found that the similarity of permeability of inner layers plays an important role in the occurrence of scale effects, which has been neglected in the most of conventional model tests. To assure the best scale effects for permeable coastal structures, control of Reynolds numbers of the porous media flow in each layer is recommended. It is also found that Reynolds numbers in revetment, filter, and core layer must be greater than $2{\times}10^4$, $3{\times}10^3$, and $1{\times}10^3$, respectively. 해안구조물(海岸構造物)의 안정성(安定性)과 사면상(斜面上)의 반사파(反射波), run-up, run-down 등 흐름특성(特性)에 대한 모형(模型)의 축척효과(縮尺?果) 발생(發生) 메카니즘과 그 제어(制御) 방법(方法)을 7종(種)의 축척모형(縮尺模型)에 의해 실험적(實驗的)으로 연구(硏究)하였다. 그 결과(結果), 종래(從來)의 많은 연구자(硏究者)들이 소홀히 해 왔던 구조물(構造物) 내부(內部)의 침투류(浸透流) 특성(特性)의 상사(相似) 여부(如否)가 축척효과(縮尺?果) 발생(發生)의 가장 중요(重要)한 요인(要因)임을 지적(指摘)하였다. 해안구조물(海岸構造物) 가운데서 특히 투과성(透過性) 구조물(構造物)의 축척효과(縮尺?果) 제어(制御)를 위해서는 피복층(被覆層), filter층(層), 피복층(被覆層)에 가까운 core부(部)의 침투류(浸透流) Reynolds수(數)가 각각(各各) Re > $2{\times}10^4$, $Re_f$ > $3{\times}10^3$, $Re_c$ > $1{\times}10^3$인 조건(條件)을 만족하도록 구조물(構造物) 각(各) 층(層)의 축척(縮尺)을 결정(決定)하는 것이 바람직함을 강조(强調)하였다.

생태계 제어 시설물의 설계 및 배치 최적화(1) -연승식 양식시설의 계류력 특성 및 동요저감에 관한 연구-

류청로,김현주,RYU Cheong-Ro,KIM Hyeon-Ju 한국수산과학회 1995 한국수산과학회지 Vol.28 No.1

To develop the optimal design method for the longline type scallop culturing facilities in the open sea numerical calculations and hydraulic model experiments are carried out for the stability and function optimization. Using the results for the motion and tension of the facilities, stable design concepts and effects of motion control system by vertical anchor and resistance discs art discussed. The results of this study that can be applied to the design are as follows: 1) Total external forces by design wave $(H_{1/3}\;=\;6,7\;m,\;T_{1/3}\;=\;12sec)$ at the coastal waters of Jumunjin for unit facility (one main line) are estimated to 5-20 tons, and required anchor weights are 10-40 tons in the case of 2-point mooring system. Though the present facilities are stable to steady currents, but is unstable to the extreme wave condition of return period of 10 years. 2) The dimensions and depth of array systems must be designed considering the ecological environments as well as the physical characteristics including the mooring and holding forces that are proportional to the length and relative depth of main line to wave length, and the number of buoys and nets. 3) Oscillation of the facility is influenced by water particle motion and the weight of hanging net, and is excited at both edge, especially at the lee side. To reduce the motion of the nets, the vertical anchoring system and the resistence disc method are recommended by the experimental results, 4) The damage of rope near the anchor by abrasion should be prevented using the ring-type connection parts or anchor chains.

연안해역의 기상${\cdot}$파랑관측망 설계 및 해석기술의 구축 - 해양파랑관측자료의 해석방법 -

류청로,김희준,손병규,Ryu Cheong-Ro,KIM Hee-Joon,SHON Byung-Kyu 한국수산과학회 1997 한국수산과학회지 Vol.30 No.1

Application of digital filter to the wave analysis is studied using the observed data by wave gauge. Sea wave data obtained from wave gauge always include long wave frequency components. In order to estimate the sea wave parameters, we must re-analyzed wave data by using a digital filter and the concept of mean sea level correction method. By the wave by wave analysis and spectral methods, sea wave parameters on the basis of wave data obtained by the conventional method and digital filter are compared. The best-fitted design filter determined by the necessary conditions of frequency responses, can be obtained by calculating various transfer functions. Thus, to get the best the digital filter design, both Butterworth filter and Savitzky-Golay filter of digital filter are used in the frequency and time domain, respectively. Three cases of observation wave data are calculated by applying digital filter. The components of different frequency bands in the surf zone are coexisted in three cases. The wave data for wind wave components is computed using the digital filter the surf zone and off-surf zone, and based on the filtered data, wave parameters are calculated by the spectral analysis and wave by wave analysis methods, respectively. As a results, when sea wave data observed by wave gauge are analyzed, the Savitzky-Golay method is recommended which can well appear cut-off frequency by experimental choosing filter length in the time domain. The better mean sea level correction method is the Butterworth filter in the frequency domain.

착저식 인공어초에 작용하는 파력특성에 관한 연구

류청로,김현주,RYU Cheong-Ro,KIM Hyeon-Ju 한국수산과학회 1994 한국수산과학회지 Vol.27 No.5

The methods to determine the hydrodynamic coefficients for the fixed type artificial reefs which were constructed to control ecological system in coastal waters are compared and discussed by model test results. To calculate the wave forces, least square method show good agreement with the experimental results and more stability than maximum force component method or Fourier decomposition method. This modified least square method of weighting the square of measured force turned out to be the most feasible method for maximum force. Using the feasible method, hydrodynamic characteristics for artificial reefs on uniform slopes offshore and breaking zone were studied. They were properly related to Keulegan-Carpenter's number and found larger than previous results. Wave force coefficients for artificial reefs around breaking zone were distributed from 1.5 to 2.5, and the mean value was 2.0. Drag force components were more in evidence than inertia force in maximum force which is important parameter to evaluate stability for high-permeability structures. A formula for the calculation of the maximum force for artificial reefs design is proposed, using structural dimension, water particle velocity and Keulegan-Carpenter's number.

유류확산모델 개발 및 동해의 유류오염 사고대책

류청로(CHEONG-RO RYU),김홍진(HONG-JIN KIM) 한국해양공학회 2005 韓國海洋工學會誌 Vol.19 No.4

There has been increasing offshore oil exploration, drilling, and production activities, as well as a huge amount of petroleum being transported by tankers and pipelines through the ocean and costal environment. Assessment must be made of the potential risk of damage resulting from the exploration, development and transportation activities. This is achieved through predictive impact evaluations of the fate of hypothetical or real oil spills. When an oil spill occurs, planning and execution of cleanup measures also require the capability to forecast the short-term and long-term behavior of the spilled oil. A great amount of effort has been spent by government agencies, oil industries, and researchers over the past decade to develop more realistic models for oil spills. Numerous oil spill models have been developed and applied, most of which attempt to predict the oil spill fate and behavior. For an actual contingency planning, the oil fate and behavior model should be combined with an oil spill incident model, an environmental impact and risk model and a contingency planning model. The purpose of this review study is to give an overview of existing oil spill models that deal with the physical, chemical, biological, and socio-economical aspects of the incident, fate, and environmental impact of oil spills. After reviewing the existing models, future research needs are suggested. In the study, available oil spill models are separated into oil spill incident, oil spill fate and behavior, environmental impact and risk, and contingency planning models. The processes of the oil spill fate and behavior are reviewed in detail and the characteristics of existing oil spill fate and behavior models are examined and classified so that an ideal model may be identified. Finally, future research needs are discussed.

한국 동남해역에서의 유출유 확산예측모델

류청로(Cheong Ro Ryu),김종규(Jong Kyu Kim),설동관(Dong Guan Seol),강동욱(Dong Uk Kang) 한국해양환경·에너지학회 1998 한국해양환경·에너지학회지 Vol.1 No.2