• Journal of the Korean Institute of Gas
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• 제19권6호
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• pp.67-71
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• 2015

Natural frequencies of a cryogenic fuel tank of LNG vehicle were computed to check the safety related to the resonances, and tests were performed to confirm the vibrational durability of a cryogenic fuel tank. There were 3 tests. The first test started at excitation frequency of 31.9Hz, and the test was performed reducing the excitation frequencies. Failure took place at 22.1Hz. The second test was performed with the frequencies to be increased. At 12.7 Hz, failure took place and nitrogen gas was exhausted. In the third test, the excitation frequencies were continuously changed, and the vibration port was failed in the range between 8 Hz and 19.3 Hz. Detailed research on the failed parts of the tank in this study is recommended to enhance the safety of the cryogenic fuel tanks of LNG vehicles.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 한국미생물생명공학회 1975년도 학술발표논문집
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• pp.111.3-111
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• 1975

항공연료인 Jet 연료에는 미생물이 용이하게 번식하여 항공기의 연료탱크, 연료계에 관계가 있는 aluminum 합금을 부식시키므로 미국, 영국, 일본 등지에서 항공연료에 오염되는 미생물을 문제시하고 있는 형편이다.(중략)

• New & Renewable Energy
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• 제2권4호
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• pp.102-106
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• 2006

에탄올은 금속, 고무 수지를 부식시키고 열화시키기 때문에 FFV 등 알코올 대응차량이 아닌 경우 에탄올 허용도가 제한되고 있으며, 물과의 상호용해성과 흡습성으로 수분혼입에 의한 상분리가 발생하여 혼합가솔린의 유통에서의 취급에 어려움이 야기되고 있다. 또한, 에탄올은 가솔린과 혼합되면 공비현상으로 인하여 50% 유출온도가 크게 떨어지고 증기압이 7kPa 정도 상승을 초래하는 점도 간과하지 않을 수 없다. 따라서, 자동차용휘발유에 에탄올을 혼입하여 사용할 경우, 가솔린기재를 적절히 선택하여 적정품질을 유지하여야 하며 무엇보다도 에탄을 혼입농도에 따른 저장탱크와 주유기 등의 부품에의 영향과 저장시의 상분리 문제를 충분히 규명하여 유통인프라에서의 적절한 대응책이 마련되어져야 한다. 유통 인프라 대응을 위해서는 우선 생산단계에서 수분 혼입을 최소화하기 위하여 저유소의 출하지점에서 서브옥탄가솔린과 에탄올을 라인브랜딩에 의해 제조하는 방법이 가장 타당하며, 수송부문에서는 탱크로리 등의 공급라인인 파이프와 실링 재질 등에 대해서 면밀한 검토가 필요하다고 할 수 있다. 주유소에서의 대응은 에탄을 혼합연료와 직접 접촉하는 연료계 등 부품재질을 내부식성의 재질로 변환시켜야 하며, 수분혼입을 최소화하기 위한 이중탱크 설치, 지하탱크 환기구내의 대기벨브 설치 등이 필요하며, 기타, 품질 및 수분관리 대책 등도 마련되어야 할 것이다.

• Corrugated packaging logistics
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• 통권91호
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• pp.78-96
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• 2010

열설비에서 회수되는 고온의 응축수를 고온수용 급수펌프를 이용하여 직접 급수시키므로 응축수탱크 및 보충수탱크에서 발생되는 재증발 증기를 Steam ejector를 이용, 흡입하여 중압으로 열사용처로 다시보내 15%이상의 에너지 절감효과 및 연료절감 효과를 볼수 있도록 하는 설비를 개발하여 소개하고자 한다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.626-629
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• 2007

Vibration originated from the fuel pump is transmitted to the fuel pump module and fuel tank. Fuel tank transmits it to chassis of vehicle. Also, noise perturbed through fuel and fuel tank is radiated out. Dynamic characteristics of fuel tank are composed of tank structure and containing fuel quantity. Therefore, this study is focused at fuel tank with various quantity. As a result, characteristics of vibration for various fuel quantity in a tank are identified as the more mass of fuel is, the less the 1st resonance frequency decrease. Also, between acoustic camera and mode shape of modal analysis are used for searching the positions of radiated noise and are found to be in accordance with each other.

• Journal of Auto-vehicle Safety Association
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• 제13권4호
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• pp.73-80
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• 2021

Recently, Korea has established a plan for the supply of hydrogen vehicles and is promoting the expansion of the supply. Risk factors for hydrogen vehicles are hydrogen leakage, jet fire, and explosion. Therefore Safety measures are necessary for this hazard. In addition, risks in semi-closed spaces such as tunnels, underground roads, and underground parking lots should be analyzed. In this study, an explosion experiment was conducted on a hydrogen tank used in a hydrogen vehicle to analyze the risk of a hydrogen vehicle explosion accident that may occur in a semi-closed space. As results, the effect on the structure and the human body was analyzed using the overpressure and impulse values for each distance generated during the explosion.

• Journal of Aerospace System Engineering
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• 제15권1호
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• pp.80-85
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• 2021

In this study, for conducting a static load test of an external fuel tank used for an aircraft, the flight load acting on the external fuel tank was converted to the test load and the suitability of the converted test loads was confirmed. In order to calculate the test load from the flight load, the external fuel tank was divided into several sections. Shear load, moment by unit shear load, and unit moment were calculated for each section. Test loads for each section were then calculated by computing the shear load, the moment of each section, and flight load condition. In actual static load tests, it might not be possible to impose the test load in the calculated position due to physical constraints. Therefore, after determining positions in which the load could be imposed in the actual test, the test load calculated for each section was redistributed to selected positions. Finally, a test load plan was established by applying a whiffle tree to enhance the efficiency of the test performance while making it easier to operate the actuator. The reliability of the test load plan was verified by comparing it with flight load conditions.

• Journal of Aerospace System Engineering
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• 제16권3호
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• pp.99-104
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• 2022

Aircraft pylon connects the engine or external stores to the main wing, and transfers the load acting on the pylon to the main structure of the aircraft. In particular, it should perform the function of separating the external store mounted on the pylon in case of emergency or mission performance. At this time, if the separation of the external store is not performed properly due to peripheral air flow or functional problems during the separation process of the external store, it may seriously impact the survivability of the aircraft. For this reason, to apply an external attachment to an aircraft, it is necessary to prove the stability of the external attachment in the separation situation in advance. In this paper, we present the result of the ground separation test performed to confirm that the external fuel tank, which is an external attachment, can be safely separated from the pylon. As a result of the test, the separation movement of the external fuel tank was measured with a high-speed camera, and the stability of the separation of the external fuel tank from the pylon were confirmed through the ground separation test. Additionally, the test result provides basic data for the stability evaluation of the separation of external attachments in actual aircraft.

• Journal of Aerospace System Engineering
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• 제17권1호
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• pp.16-23
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• 2023

The aircraft fuel system performs a number of functions such as supplying fuel, transferring fuel between fuel tanks, and measuring the amount of residual fuel in each fuel tank. Since it is a direct cause of fire hazard in crash incident, it is a must to improve survivability of crew members by designing the airframe to tolerate expected crash impact. The civil aviation authority requires intensive verification of the fuel system design to determine precise application of the airworthiness requirement. Research activity on airworthiness certification criteria and verification scheme is still insufficient, although it has a significant importance. In this paper, as part of a study to improve flight safety by developing guidelines for demonstrating fuel system crash resistance, analysis results of fuel system crash-related airworthiness certification standards, verification scheme, and cases study applicable to military rotorcraft have been reviewed.

• Journal of the Korean Institute of Gas
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• 제15권6호
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• pp.57-62
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• 2011

In this study, the optimized design for 130 liter storage fuel tank with 70MPa filling pressure has been investigated using a FEM technique and Taguchi design method. The strength safety of a composite fuel tank in which is fabricated by an aluminum liner of 6061-T6 material and carbon fiber wound composite layers of T800-24K has been analyzed based on the criterion of design safety of US DOT-CFFC and Korean Standard. The FEM computed results on the stress safety of 70MPa hydrogen gas tank were compared with a criterion of a stress ratio, 2.4 of US DOT-CFFC and Korean Standard, and indicated the safety. Thus, the optimized design elements based on the Taguchi's method were recommended as an aluminum liner thickness of 6.4mm, a carbon fiber laminate thickness in hoop direction of 31mm and a carbon fiber laminate thickness in helical direction of 10.2mm, which is represented by a design model of No. 5.