• 한국컴퓨터정보학회:학술대회논문집
• /
• 한국컴퓨터정보학회 2023년도 제68차 하계학술대회논문집 31권2호
• /
• pp.7-10
• /
• 2023

최근 기후 변화가 심각해짐에 따라 수소 에너지에 대한 관심이 집중되고 있으며 이를 안전하게 운송/보관할 수 있는 용기에 대한 연구도 활발히 진행되고 있다. 특히 고압 가스를 저장하는 TypeIII 용기의 노후화 및 안전과 관련되어 결함을 인지하는 연구가 활발하다. 그러나 이 용기의 외각층을 이루는 CFRP 소재는 탄소 섬유와 에폭시가 복잡한 구조로 구성되어 결함별 탐지가 매우 어렵다. 본 논문에서는 음향방출시험과 딥러닝을 활용하여 CFRP 결함 데이터셋을 구축하고 이를 분류할 수 있는 모델을 제안한다. 특히 CFRP 시편을 직접 제작하여 AE 센서를 부착하고 파괴하여 파형 데이터를 수집하였다. 이후 표현 학습을 통해 데이터의 특징을 압축/추출하고 유사도를 비교해 결함별 데이터를 판별하는 알고리즘을 개발하였다. 구축된 데이터셋의 실루엣 계수는 0.86으로 높은 군집도를 보였다. 마지막으로 구축된 데이터셋을 실시간으로 분류할 수 있는 1D-CNN 딥러닝 모델을 개발하였으며 99.33%의 높은 분류 정확도를 보였다.

• 한국수소및신에너지학회논문집
• /
• 제34권1호
• /
• pp.26-31
• /
• 2023

In this study, in order to propose a modular method for type IV high aspect ratio modular hydrogen storage vessel, a numerical analysis was conducted on the heat transfer behavior in series and parallel connection methods, and the differences according to each connection method were reviewed. Computational fluid dynamics software was used to check the internal temperature and pressure values of the hydrogen storage container under charging conditions. In terms of thermal safety when charging hydrogen gas, it was confirmed that the parallel modularization method was superior.

• 한국수소및신에너지학회논문집
• /
• 제33권2호
• /
• pp.158-163
• /
• 2022

The test method on the Type II high-pressure hydrogen storage tanks made of the metal wire hoop winding is a complex and high risk. Also closeup on the tank being test is difficult. In this study, we studied a mechanical test method for a high-pressure hydrogen tanks. This method must be simple, risk-free and possible to observe the change in microscopic behavior of a metal wire on a liner. As the results, it was possible to observe the microscopic behavior on the metal wire by the mechanical test method. Also, a simple and risk-free test was possible compared to the conventional test method for high pressure hydrogen tanks.

• 한국수소및신에너지학회논문집
• /
• 제13권2호
• /
• pp.110-118
• /
• 2002

The hydrogen storage vessel having a good heat conductivity along with a simple structure and a low cost for these alloys was designed and manufactured, and then its characteristic properties were studied in this study. The various parts in hydrogen storage vessel consisted of copper pipes and stainless steel of 250 mesh reached the setting temperature after 4~5 minutes, which indicated that storage vessel had a good heat conductivity that was required in application. And also the storage vessel had a good property of hydrogen transport considering that the reaction time between hydrogen and rare-earth metal alloys in storage vessel was found to be within 10 min at $18^{\circ}C$ under 10 atmospheric pressure. It showed that the average capacity of discharged hydrogen volume was found to be $120{\ell}$ for $MmNi_{4.5}Mn_{0.5}$ under discharging conditions of $40^{\circ}C{\sim}80^{\circ}C$ at a constant flow rate of $5{\ell}$/min. It was found that the optimum discharging temperature for obtaining an appropriate pressure of 3atm was determined to be $60^{\circ}C$ for $MmNi_{4.5}Mn_{0.5}$ hydrogen storage alloy.

• 한국수소및신에너지학회논문집
• /
• 제16권3호
• /
• pp.284-289
• /
• 2005

Thermal analysis of cryogenic-capable vessels with insulations have been carried out to store liquid hydrogen($LH_2$). The combined insulations of MLI(Multi-Layer Insulation) and VCS(Vapor-Cooled Shield) under high vacuum are considered in the analysis for various volumes of vessels. Vapor-Cooled Shields(VCS) are installed at cylinder wall as well as disc side of the $LH_2$ vessels. The results indicate that optimal distribution of boiloff vapor from $LH_2$ vessel into two sides of VCS exists based on the evaporation loss. As the volume of $LH_2$ vessel is increased, mass flow rate of boiloff is increased while the evaporation loss per unit volume is decreased.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2007년도 추계학술대회 논문집
• /
• pp.193-196
• /
• 2007

We developed and tested the high pressure hydrogen gas cylinder(type4) for fuel cell vehicle. The working pressure is 350bar. We conducted material tests, production tests and design qualification tests on the developed cylinders according to modified NGV2-2000(hydrogen). The high pressure hydrogen gas cylinder met all the design qualification requirements of ANSI/CSA NGV2-2000 and acquired NGV2 certification from independent inspection agency.

• 한국가스학회지
• /
• 제16권6호
• /
• pp.29-33
• /
• 2012

이 연구에서는 최근의 액체수소안전관련 연구현황을 간략히 살펴보고자 한다. 액체수소 저장용기가 파손되어 액체수소가 누출될 수 있다. 누출된 액체수소는 풀을 형성하고 증발하여 수소증기 운을 형성한 뒤 증기운 폭발이 일어날 수 있다. 액체수소를 저장하고 있는 용기가 외부로부터 유입되는 열에 의하여 증발하는 가스를 처리하지 못할 경우에는 BLEVE가 발생할 수 있다. 압축된 수소가스가 있는 시설에서는 수소누출에 의한 제트화제가 발생하고 지연점화에 의하여 개방공간에서 플래시 화재 및 폭발이 발생할 수 있다. 이러한 여러 가지 사건에 대하여 최근의 기술개발과 향후연구개발 방향에 대하여 간략히 살펴보았다.

• 한국수소및신에너지학회논문집
• /
• 제34권3호
• /
• pp.274-282
• /
• 2023

This study conducted direct numerical simulations of the natural convection phenomena of gaseous hydrogen in a physical storage container containing four circular cylinders. Rayleigh numbers (Ra) in the range of 10⁴≤Ra≤10⁶ and a Prandtl number (Pr)=0.69 (gaseous hydrogen) were considered. The main parameter is a horizontal distance of four circular cylinders and the values of ε_h=0.1, 0.2, 0.3, 0.4, and 0.5 are considered. The flow and thermal structures and corresponding heat transfer characteristics are investigated with respect to the transition of the flow regime. The time- and surface-averaged Nusselt number on the cylinder surface and the wall of physical storage container increased by about 57% and 69% according to the Ra and ε_h, respectively. Thus, the horizontal distance has an influence on the heat transfer characteristics on natural convection of gaseous hydrogen.

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2003년도 춘계학술발표대회 요약집
• /
• pp.294.2-294.2
• /
• 2003

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 2001년도 추계학술발표회요약집
• /
• pp.292.2-292
• /
• 2001