• 항공우주시스템공학회지
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• 제16권1호
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• pp.70-80
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• 2022

공중급유 능력은 항공기의 임무시간 증대와 운용영역 확장을 제공함에 따라 많은 군용기에 적용 및 운영되어왔다. 피급유기가 지정된 급유기로부터 공중급유를 받기 위해서는 기술 및 운용호환성평가를 통해 공중급유허용을 확보해야 한다. 적합성 평가에는 공중급유 조종성, 기능성, 연료, 조명시스템 평가를 포함하고 있으며 비행시험을 통해 최종 검증된다. 그러나 한국에서는 신규개발항공기에 대한 공중급유 적합성 평가를 수행한 사례가 없기 때문에 시험 요구도, 범위 및 프로그램 규모를 결정하기 위한 경험이 없는 상황이다. 본 논문에서는 공중급유 유형 소개와 한국 공군에 도입된 Boom & Receptacle 시스템에 대한 고정익 항공기 공중급유 FCS (Flight Control System) OFP (operational flight program) 검증, 시스템 검증 및 영역 허용 관련 공중급유 비행시험 방법을 연구하였다.

• Korean Chemical Engineering Research
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• 제61권4호
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• pp.611-618
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• 2023

전 세계에서 수소자동차 충전의 기초로 사용되는 SAE J2601의 내용과 충전 프로토콜의 목적과 개념을 조사하고, 우리나라의 프로토콜 관련 연구 내용을 조사하였다. 그리고, 우리나라에서 개발한 수소 충전 성능평가 장비의 구성 요소와 수소충전소의 성능과 안전을 평가할 수 있는 방법에 대해 검토하고, 현재 국내에서 운영하고 있는 수소충전소에 대해 현장 적용을 실시하였다. 또한, 국내에서 운영 중인 수소충전소에서 수집한 데이터를 이용하여 경제성 분석을 하였다. 수소충전소의 안전성과 경제성을 확보하기 위해서는 프로토콜을 만족하여야 하며, 프로토콜을 만족하기 위해서는 충전온도, 충전압력, 충전 유량이 안전한 범위 내에서 제어되고 있는지 평가하는 것이 필요하다.

• 한국수소및신에너지학회논문집
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• 제32권5호
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• pp.299-307
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• 2021

In order to expand the supply of hydrogen vehicles, the first thing to be done is to build an infrastructure to supply hydrogen. There are fixed and mobile types of hydrogen refueling stations that can supply hydrogen. Mobile hydrogen refueling stations have the advantage of supplying hydrogen to two or three areas, so the introduction of mobile hydrogen refueling stations is considered at the initial stage of hydrogen vehicle dissemination. However, mobile hydrogen refueling stations have greater risks than fixed hydrogen refueling stations due to the hazard associated with movement and intensive installation of facilities in vehicle, so stricter design standards to lower the risk must be applied. Therefore, in this study, basic data for establishing safety standards for mobile hydrogen refueling stations were proposed by suggesting improvements such as the location of emergency shutoff valves, the number of gas detectors etc., using HAZOP analysis.

• 문화기술의 융합
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• 제10권5호
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• pp.797-802
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• 2024

수소충전소 장비 설치, 시운전과 고장 수리할 때 수소충전소 안전이 가장 취약하다. 이때 수소충전소의 디지털트윈을 개발하여 제공하면 장비 설치, 시운전과 고장 수리하는데 도움이 될 수 있다. 그리고 수소충전소 운영 중에, 이벤트 검출, 원인 분석과 예측을 위해서도 디지털트윈이 필요하다. 그러나 현재 수소충전소의 SCADA HMI는 2D로 구성되어 있으므로, 수소충전소에 대한 기본 지식과 구성 현황을 알지 못하는 사람들은 직관적으로 이해하기 어렵다. 본 논문에서는 수소충전소에 디지털트윈 기술을 도입하여 수소충전소 장비에서 측정된 값을 3D로 실시간으로 표시하여, 수소충전소의 이벤트 발생, 원인 분석과 예측을 직관적으로 하는데 도움을 주고자 한다. 이를 위해 SCADA HMI에서의 데이터를 추출하였고, 이 데이터를 디지털트윈에 전송하였으며, 디지털트윈에서 직관적이고 이해하기 쉬운 3D환경을 제공하여, 비전문가도 수소충전소의 운영 현황을 쉽게 파악할 수 있도록 구현하였다.

• 한국수소및신에너지학회논문집
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• 제34권3호
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• pp.297-306
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• 2023

The frequency of fatal accidents that can occur at hydrogen refueling station was compared with the risk criterion for the general public suggested by the health and safety executive. If hydrogen refueling station meets the accident prevention facility standards presented in KGS Code FP216/217, it was confirmed that the risk of hydrogen refueling station was not at an unacceptable (intolerable) risk level. However, the risk of hydrogen refueling station due to small leak was analyzed as low as reasonably practicable. Therefore, methods for improving the safety instrumented function of hydrogen refueling station were reviewed. It was confirmed that the risk of hydrogen refueling station can be affected by the number of installed safety instrumentation system components, redundant architecture, mission time, proof test interval, etc. And methods for maintaining the risk of hydrogen refueling station at an acceptable risk level have been proposed.

• 한국수소및신에너지학회논문집
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• 제27권3호
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• pp.256-263
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• 2016

As the hydrogen era comes near future, hydrogen fuel cell vehicles are core of hydrogen economy. Until now, Korea has 17 hydrogen refueling stations but 9 hydrogen refueling stations have been retired already and 8 hydrogen refueling stations are still running. With a limited number of hydrogen refueling stations, it is very difficult to get scientific data for the economy of hydrogen refueling stations in Korea. Thus, based on NREL(National Renewable Energy Laboratory) study, we analyzed most recent data for the construction of hydrogen refueling stations in one specific site in Korea. The cost comparison data between Korea and USA shows 14% difference, saying higher costs of Korea. Korea looks 5 years delay compared to USA. This data will be an important tool for the investment from every industrial parties.

• 한국수소및신에너지학회논문집
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• 제35권3호
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• pp.300-309
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• 2024

Hydrogen utilization in the transportation sector, which relies on fossil fuels, can significantly reduce greenhouse gas by using to hydrogen fuel cell vehicles, and its adoption depends performance of hydrogen refueling station. The present study developed a model to simulate the back-to-back filling process of heavy duty hydrogen fuel cell vehicles at hydrogen refueling stations using a cascade method. And its quantitatively evaluated hydrogen refueling station performance by simulating various mass flow rates and storage tank capacity combinations, analyzing vehicle state of charge (SOC) of vehicles. In the cascade refueling system, the capacity of the high-pressure storage tank was found to have the greatest impact on the reduction of filling time and improvement of efficiency.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(1)
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• pp.41-47
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• 1995

A parametric study bas been performed for the various refueling schemes of CANDU 6 reactor loaded with reference DUPIC fuel. The optimum discharge burnup was determined such that the peak bundle power is minimized for the equilibrium core. Based on the results of instantaneous core calculation using patterned random age distributions, it was decided to perform the refueling simulations only for 2-bundle and 4-bundle shift refueling schemes. The 600 FPD simulation has shown that the operational margins of the channel and bundle power to the license limits are 7.9% and 17.1%, respectively, for 2-bundle shift refueling scheme. The 4-bundle shift refueling scheme also satisfies the license limits and the operational margins of the channel and bundle power are 7.1% and 9.8%, respectively. The result of refueling simulation indicate the possibility of using reference DUPIC fuel in current CANDU 6 reactor.

• Nuclear Engineering and Technology
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• 제45권2호
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• pp.257-264
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• 2013

In Canada Deuterium Uranium (CANDU)-type nuclear power plants, the reactor is composed of 380 fuel channels and refueling is performed on one or two channels per day. At the time of refueling, the fluid force of the cooling water inside the channel is exploited. New fuel added upstream of the fuel channel is moved downstream by the fluid force of the cooling water, and the used fuel is pushed out. Through this process, refueling is completed. Among the 380 fuel channels, outer rows 1 and 2 (called the FARE channel) make the process of using only the internal fluid force impossible because of the low flow rate of the channel cooling water. Therefore, a Flow Assist Ram Extension (FARE) tool, a refueling aid, is used to refuel these channels in order to compensate for the insufficient fluid force. The FARE tool causes flow resistance, thus allowing the fuel to be moved down with the flow of cooling water. Although the existing FARE tool can perform refueling in Korean plants, the coolant flow rate is reduced to below 80% of the normal flow for some time during refueling. A Flow rate below 80% of the normal flow cause low flow rate alarm signal in the plant operation. A flow rate below 80% of the normal flow may cause difficulties in the plant operation because of the increase in the coolant temperature of the channel. A new and improved FARE tool is needed to address the limitations of the existing FARE tool. In this study, we identified the cause of the low flow phenomena of the existing FARE tool. A new and improved FARE tool has been designed and manufactured. The improved FARE tool has been tested many times using laboratory test apparatus and was redesigned until satisfactory results were obtained. In order to confirm the performance of the improved FARE tool in a real plant, the final design FARE tool was tested at Wolsong Nuclear Power Plant Unit 2. The test was carried out successfully and the low flow rate alarm signal was eliminated during refueling. Several additional improved FARE tools have been manufactured. These improved FARE tools are currently being used for Korean CANDU plant refueling.

• 한국추진공학회지
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• 제15권3호
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• pp.80-85
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• 2011

연료탱크 내부에 존재하는 공기는 저장 중 연료의 산화를 유발하고, 연료 이송성능을 저하시킬 수 있다. 따라서 항공기 연료탱크의 주유절차를 개선하기 위하여 연료탱크 내부에 존재하는 공기를 줄이는 방안으로 진공주유방식을 제안하였다. 본 논문에서는 진공주유 절차를 수립하여 실제 시험을 수행해 보았고, 이를 통해 진공 주유 중 발생하는 현상을 관찰할 수 있었다. 또한 탱크 내부의 기포 및 주유시간 절감을 위하여 다른 개선된 방안을 제안하였다.