• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.3
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• pp.76-83
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• 2017

Korea Aerospace Research Institute(KARI) has been developing a new launch vehicle Korea Space Launch Vehicle-II(KSLV-II) with their own technology. Thus, it is required a new launch complex that corresponds to a new propulsion system of launch vehicle. Because widely changing of KSLV-II comparing with KSLV-I such as thrust of engine system, composition of vehicle staging, pneumo-hydraulic scheme of propulsion system, it is important to establishing appropriate ground support equipments for fuel(kerosene) filling. In this critical design process, specific supply line and specification of components are designed and the concept of kerosene filling is determined based on results of preliminary design. Also, plans of supply operation and prerequisite are established and operation algorithms are formed.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.6
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• pp.46-51
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• 2012

Fuel Cell Hybrid Vehicles (FCHVs) have become a major topic of interest in the automotive industry owing to recent energy supply and environmental problems. Several types of power management strategies have been developed to improve the fuel economy of FCHVs including optimal control strategy based on optimal control theory, rule-based strategy, and equivalent consumption minimization strategy (ECMS). The ECMS is applied in this study. This strategy is based on the heuristic concept that the usage of the electric energy can be exchanged to equivalent fuel consumption. This strategy is known as one of the promising solutions for real-time control of hybrid vehicles. The ECMS for an FCHV is introduced in this paper as well as the equivalent fuel consumption parameter. The relationship between the battery final state of charge (SOC) and the fuel consumption while changing the equivalent fuel consumption parameter is obtained for three different driving cycles. The function of the equivalent fuel consumption parameter is also discussed.

• Journal of the Korean Society of Systems Engineering
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• v.2 no.1
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• pp.37-41
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• 2006

The KSLV-I satellite launch vehicle will be launched in a space center currently under construction. The Space Center which is an advance post base of space development of Korea is located on Oenaro island in Kohung, South Cholla Province. A Ground Complex of the Space Center consists of an AC(Assembly Complex), a LC(Launch Complex), and a MCC(Mission Control Center). Assembly and test facilities are located in the AC in which stage assembly, integrated assembly, check-up, certification test, and pre-launch test are made effectively. A launch pad, fuel supply facilities, a launch control center and associated supporting facilities are located in the LC, and the MCC has control over the space center. These ground complex facilities have diverse forms of an interface with mechanical device, electric device, and etc. These should also provide optimum condition and performance during launch operation processes of the launch vehicle. This paper introduces the result of R&D for the AC of the ground complex performed during system design period.

• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.250-256
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• 2013

Gasoline generates organic acid and polymer (gum) by hydrocarbon oxidation depending on the storage environment such as temperature and exposure to sunlight, which can cause metal corrosion, rubber and resin degradation and vehicle malfunction caused by accumulation in fuel supply system. The gasoline which has not been used for a long time in bi-fuel (LPG-Gasoline) vehicle causes problems, and low octane number gasoline have evaporated into the field, but the exact cause has not been studied yet. In this study, we suggest a plan of quality management by investigating the gasoline oxidation behavior. In order to investigate the oxidation behavior of gasoline, changes of gasoline properties were analyzed at various storage conditions such as storage time, storage vessel type (vehicle fuel tank, PE vessel and Fe vessel) and storage circumstances (sunlight exposure and open system, etc.). Currently distributing gasoline and bioethanol blended fuel (blended 10%) were stored for 18 weeks in summer season. The sample stored in PE vessel was out of quality standard (octane number, vapor pressure, etc.) due to the evaporation of the high octane number and low boiling point components through the vessel cap and surface. Especially, the sunlight exposure sample stored in PE vessel showed rapid decrease of vapor pressure and increase of gum. Bioethanol blended fuel showed similar results as gasoline.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.6
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• pp.619-626
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• 2016

The new 1.4 L turbocharged LPG direct injection (T-LPDI) engine is presented in this paper to improve the fuel efficiency of the vehicles installed with the 2.0 L LPG port fuel injection (LPI) engine, while maintaining the performance as a downsizing concept for the new engine platform development. Firstly, the return type high pressure LPG fuel supply system is designed and mounted in the new 1.4 L T-LPDI engine. As a result, this new engine shows a much better WOT performance and approximately 8 % of improved fuel economy level, as compared to the 2.0 L LPI vehicle. Secondly, the LPDI engine specific optimized design for high pressure fuel components and fuel injection control strategies are proposed and evaluated in order to overcome the restartability problem in a heat-soaked condition called the vapor lock phenomenon. Consequently, these experimental results illustrate a great potential for the developed 1.4 L T-LPDI engine as a possible substitute for the 2.0 L LPI engine.

• Transactions of the Korean hydrogen and new energy society
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• v.13 no.4
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• pp.330-338
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• 2002

A long-term energy system in the future is expected to be based on the ideal circulation system between water and hydrogen in the sense that the hydrogen prepared from water eventually returns to water again after its use. Currently, with respect to the hydrogen energy system, it is predicted that the turning-point at which the production cost of hydrogen will become to be lower than that of fossil fuels would be after 2010. However, fuel cell technology would be able to be practically used for the applications to the transportation vehicles and small-scale power sources from 2004, and therefore, an efficient construction of the infrastructure covering hydrogen production and supply systems would be required with short-/mid-term technologies for the $CO_2$ reduction associated with fossil fuel utilization. In this paper, the hydrogen quantity available in domestic market has been estimated focusing on the hydrogen by-produced from domestic industries, and also the infrastructure for hydrogen-driven vehicles like fuel cell cars has been reviewed.

• Journal of the Korean Institute of Gas
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• v.11 no.4
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• pp.12-16
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• 2007

The fuel pressure regulator mounted on CNG vehicles is used to maintain a constant pressure in the fuel injection system. It needs precise fuel pressure control to obtain benefits of high efficiency and low emissions in CNG vehicles. In this study, a high pressure test rig for the performance evaluation of CNG regulators was introduced. Two different CNG regulators were tested and compared each other at various test conditions. Results showed that dynamic response and creep characteristics are directly effected by the valve assembly design. Gas temperature was dramatically dropped at hish supply pressure conditions, so that effective design for coolant bowl is needed to prevent icing problem.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.73.1-73.1
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• 2010

For the successful cold starting of a fuel cell engine, either internal of external heat supply must be made to overcome the formation of ice from water below the freezing point of water. In the present study, switchable vanadium oxide compounds as variable temperature-electrical resistance materials onto the surface of flat metallic bipolar plates have been prepared by a dip-coating technique via an aqueous sol-gel method. Subsequently, the chemical composition and micro-structure of the polycrystalline solid thin films were analyzed by X-ray diffraction, X-ray fluorescence spectroscopy, and field emission scanning electron microscopy. In addition, it was carefully measured electrical resistance hysteresis loop over a temperature range from $-20^{\circ}C$ to $80^{\circ}C$ using the four-point probe method. The experimental results revealed that the thin films was mainly composed of Karelianite $V_2O_3$ which acts as negative temperature coefficient materials. Also, it was found that thermal dissipation rate of the vanadium oxide thin films partially satisfy about 50% saving of the substantial amount of energy required for ice melting at $-20^{\circ}C$. Moreover, electrical resistances of the vanadium-based materials converge on an extremely small value similar to that of pure flat metallic bipolar plates at higher temperature, i.e. $T{\geq}40^{\circ}C$. As a consequence, experimental studies proved that it is possible to apply the variable temperature-electrical resistance material based on vanadium oxides for the cold starting enhancement of a fuel cell vehicle and minimize parasitic power loss and eliminate any necessity for external equipment for heat supply in freezing conditions.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.1
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• pp.47-60
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• 2021

Hydrogen is a next-generation energy source, and according to the roadmap for activating the hydrogen economy, it is expected that industries to stably produce, store, and transport of hydrogen as well as the supply of hydrogen fuel cell vehicles will be made rapidly. Accordingly, safety measures for accidents of hydrogen vehicles in confined spaces such as tunnels are required. In this study, as part of a study to ensure the safety of hydrogen fuel cell vehicles in road tunnels, a basic investigation and research on the risk of fire and explosion due to gas leakage and hydrogen tank rupture among various hazards caused by hydrogen fuel cell vehicle accidents in tunnels was conducted. The following results were obtained. In the event of hydrogen fuel cell vehicle accidents, the gas release rate depends on the orifice diameter of TPRD, and when the gas is ignited, the maximum heat release rate reaches 3.22~51.36 MW (orifice diameter: 1~4 mm) depending on the orifice diameter but the duration times are short. Therefore, it was analyzed that there was little increase in risk due to fire. As the overpressure of the gas explosion was calculated by the equivalent TNT method, in the case of yield of VCE of 0.2 is applied, the safety threshold distance is analyzed to be about 35 m, and number of the equivalent fatalities are conservatively predicted to reach tens of people.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.1
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• pp.76-86
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• 2015

KSLV-II, a new launch vehicle of Korea, requires a new launch complex(LC) for its own and proper launch operations. The new launch complex will be constructed in NARO Space Center neighboring KSLV-I launch complex for maximizing operation efficiency and economic matters. The launch complex consists of three ground support equipments, i.e., mechanical, electrical, and fuel in general. The fuel ground support equipment could be defined as a combination of systems for storage and supply of propellants and gases which are required by a launch vehicle. The compositions, functions and capabilities of fuel ground support equipment are introduced in this paper. In addition, basic design results of flame deflector configurations are included.