• Journal of the Korean Institute of Gas
• /
• v.11 no.1 s.34
• /
• pp.46-50
• /
• 2007

The metering systems in LPG vaporizers have been frequently exposed to severe conditions and resulted in many problems such as gauge malfunctioning and rupturing if the check-floaters fail to stop liquid outflow when the heat supply for the vaporization of LPG is interrupted. Therefore, to analysis the vaporizer system we carried out the vaporizer performance test and float bulb test by newly devised test equipments. Consequently, we determined the specific gravity of the float bulb and reasonable operating temperature ranges for the LPG and heating waters.

• Journal of the Korean Institute of Gas
• /
• v.19 no.3
• /
• pp.32-37
• /
• 2015

The boil-off-gases(BOG) in cryogenic LNG storage tanks are generating continuously due to the heat leakage and need to be re-liquefied by the effective way. As the present method to reliquefy BOG is using LNG cold energy to be supplied after low pressure primary pump, the demand of LNG flow rate should be over 10 times of BOG produced rate to reliquefy it. This research invented new effective re-liquefaction system having only 3~4 times of LNG flow rate against unit BOG, that the pre-liquefaction process of NGL and the use of high pressure LNG cold energy after secondary pump. By the analysis, it could be high efficient reliquefying system for all amount of BOG treatment even during the summer time, and improvement of operation safety and efficiency of LNG terminal.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2011.11a
• /
• pp.505-509
• /
• 2011

The combustion chamber and nozzle of a liquid rocket engine should be protected from the high temperature combustion gas generated by the chamber. An upper-stage nozzle extension has a large expansion ratio, therefore, The light-weight refractory materials have been used since the weight impact on the launcher performance is crucial. Gas film cooling and ablative cooling methods were used before, but were not applicable nowadays. Radiative cooling method with niobium alloy, Ni-based superalloy and ceramic based composite has been used to this day.

• Proceedings of the Membrane Society of Korea Conference
• /
• 1997.10a
• /
• pp.61-64
• /
• 1997

1. 서론 : 적절한 이산화탄소의 분리는 지구온난화의 가속현상을 늦출 수 있을 뿐만 아니라 각종 탄화수소가스의 원료로 분리 정제된 이산화탄소를 재이용할 수 있으므로 경제적으로 매우 중요하다. 이산화탄소 분리에 사용되던 기존 공정들의 단점을 보완할 수 있는 대체방안으로 최근에 개발되기 시작한 것이 소수성의 다공성 고분자 분리막(hydrophobic porous ploymeric membrane) 방법인데, 이는 모듈의 유효 막 표면적이 상대적으로 크고 기체와 액체의 흐름을 독립적으로 제어할 수 있으므로 범람 등의 현상이 없으나 막 자체의 저항이 비교적 큰 단점을 가지고 있다. Qi와 Cussler는 이러한 특성을 가지는 중공사막 모듈에서의 기-액 흐름에 대한 물질전달 상관관계식을 얻었으며[1], Karoor 등은 여러 가지 중공사막 모듈을 사용하여 순수물과 diethanolamine(DEA) 등의 흡수제에 대한 이산화탄소의 물질전달 거동을 수치모델과 실험을 통하여 고찰하였다[3]. 또한 중공사막 접촉기의 실제적 응용에 대하여 Matsumoto 등은 화력발전소에서 발생하는 연소가스 내의 이산화탄소 흠수에 대한 연구를 수행하였다[4]. 본 연구에서는 중공사막 접촉장치를 사용하여 흡수제를 순수물과 탄산칼륨($K_2CO_3$)을 사용했을 경우의 이산화탄소의 분리 거동을 수치모델과 실험을 통하여 고찰하였다. 수치모델의 경우 이전까지의 연구가 반응이 없는 경우나 반응식을 간략화시킨 경우에 한정되었는데 비하여, 반으이 있는 경우 각각의 반응물질들의 거동을 고려한 반응식을 유도하여 해를 구하고자 하녔다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2006.11a
• /
• pp.175-178
• /
• 2006

A numerical study for spray combustion of fluctuated fuel and oxidizer droplets injected into combustion chamber has been conducted for the analysis of spray combustion considering characteristics of injector. The 2 dimensional unsteady state flow fields have been calculated by using QUICK Scheme and SIMPLER Algorithm. As the spray model, DSF model and Euler-Lagrange Scheme have been used. The sine Auction has been used for droplet fluctuation model of fuel and oxidizer, while the coupling effects of the droplets between gas phase and evaporated vapor have been calculated by using PSIC model.

• Journal of the Korean Institute of Gas
• /
• v.10 no.1 s.30
• /
• pp.26-31
• /
• 2006

For the purpose of evaluating the availability of manifold safety devices installed in the LPG(Liquefied Petroleum Gas) refuelling stations, the quantitative analysis of the frequency on BLEVE(Boiling Liquid Expanding Vapor Explosion) scenario was performed. The amount of frequency reduction was the way of assessing safety devices availability. In this analysis, we could find out what sorts of safety devices are essential to satisfy acceptable social risk criteria and are prioritized to install in the future.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.30 no.5
• /
• pp.479-483
• /
• 2010

9% nickel alloy steels used for LNG, cryogenic liquid, storage tank are welded with dissimilar Inconel or Hastelloy welding rod and the weldment shows similar characteristic with the dissimilar metal weld of low carbon steel and austenitic stainless steel. Band type indications are sometimes shown on the film during radiography test of the weldments. Thus this study identified whether the indications are non-relevant indications through material, radiographic test, ultrasonic test, liquid penetrant test and microstructure analysis and also proposed radiography film interpretation and cause of band type indications.

• Aerospace Engineering and Technology
• /
• v.11 no.1
• /
• pp.91-97
• /
• 2012

The structural analyses and experimental results for the bellows of a gas-generator liquid oxygen shut-off valve were presented. The bellows experiences axial compression and external high pressure loadings at cryogenic temperatures. The analyses were performed using EJMA (Expansion Joint Manufacturing Association) standard and the commercial FE (finite element) analysis program, Abaqus v6.9, at room and cryogenic temperatures. The spring modulus, the induced stress and the expected fatigue life of the bellows were compared respectively. The effects by the contact and the material plasticity on the FE analysis results were also analyzed. Also, FE analyses related to a burst test were presented.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.18 no.10
• /
• pp.2797-2804
• /
• 1994

This paper analyzes the behaviors of corrugated membrane under the cryogenic liquid pressure and thermal loading using the FEM analysis program MARC. The FEM calculations were carried out on the basis of measured data of Technigaz membrane. It is very important to know the concentration levels and distributions of stress in the corrugated membrane. A quarter of the membrane sheet in place of the whole membrane was simulated because of its geometric symmetricity. The calculated results of the concentrated stress showed that the maximum stress occurs at the knot parts and at the root corner radius of the corrugations. The FEM calculated results indicated that the ring knot membrane which was developed in this study showed uniformly distributed stress and the lowest stress levels in the cross knot area in comparison with other two membranes. These results are very important to optimize the shape and improve the safety of membrane structure.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2007.04a
• /
• pp.358-361
• /
• 2007

Most aircraft cruise in the stratosphere at which temperature is below $-50^{\circ}C$ md, as a result, the surface of aircraft can be iced up. Ice on the wing can change aerodynamic characteristic and results in the deterioration of its performance. Ice on the engine inlet increases the possibility of compressor blade damage and affects the performance and safety of the engine. This paper focused on the development of icing simulation device for analyzing effect of icing on engine performance. Icing simulation tests were conducted with a liquid air system and a icing simulation device and results show that icing could be simulated with this system.