• Journal of Aerospace System Engineering
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• v.10 no.1
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• pp.66-73
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• 2016

Space propulsion system produces required thrust for satellites and space launch vehicles by using chemical reactions of a liquid fuel and a liquid oxidizer typically. For example, monomethylhydrazine-dinitrogen tetroxide, liquid hydrogen-liquid oxygen and RP-1-liquid oxygen are conventional combinations of liquid propellants used for the liquid propulsion system. Among several liquid propellants, the monomethylhydrazine is expecially preferred for a satellite fuel due to its better storability in liquid phase during a relatively long mission period under a space environment. Thus, a development importance of a bipropellant system using the monomethylhydrazine fuel is recognized recently as the national space program proceeds on a large scale. The objective of the present study is to review a foreign research trend of a thermal decomposition reaction of monomethyhydrazine to understand a fundamental basis of its chemical reaction to prepare for domestic development in future.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.521-523
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• 2004

The Japan Aerospace Exploration Agency (JAXA) has proposed new vertical take-off and landing (VTOL) aircraft known as the Jet-VTOL aircraft shown in Fig.1. The Jet-VTOL aircraft is based on a canard wing configuration. The aircraft has the clustered lift-fans mounted near the center of gravity for vertical flight, and has the clustered fans mounted beside the vertical tail for cruise flight. Both fans are driven by the core engine mounted inside the aft end of fuselage. The propulsion system is innovative and attractive not to be seen even in the world.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.66-71
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• 2008

Two cases with circumferential grooves were designed for a transonic compressor, and 3-D numerical simulations were conducted for stall mechanism at three representative speeds. A conclusion can be drawn from the comparison between compressors with or without casing treatment that: with the rising of rotation speed, stall margin increases dramatically under the help of casing treatments, and the case with middle grooves has reasonable compromise between stall margin increment and efficiency cutting. At lower speed, the increment reduces, and grooves at the back of blade tip have more influence on stall margin. Further investigation shows there is a transition in mechanism of compressor stall with the decline of rotational speed: at high rotation speed, the expansion of stall margin mainly results from the suppression of tip leakage vortex by casing treatments, yet it benefits more from the depression of boundary layer separation from suction surface of blade tip.

• 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.

• Advances in aircraft and spacecraft science
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• v.6 no.5
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• pp.427-442
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• 2019

Small satellites represent an emerging opportunity to realize a wide range of space missions at lower cost and faster delivery, compared to traditional spacecraft. However, small platforms, such as CubeSats, shall increase their actual capabilities. Miniaturized electric propulsion systems can provide the satellite with the key capability of moving in space. The level of readiness of miniaturized electric propulsion systems is low although many concepts have been developed. The present research intends to build a flexible test platform for the assessment of selected small propulsion systems in relevant environment at laboratory level. Main goal of the research is to analyze the mechanical, electrical, magnetic, and chemical interactions of propulsion systems with the modern CubeSat-technology and to assess the performance of the integrated platform. The test platform is a 6U CubeSat hosting electric propulsion systems, providing mechanical, electrical and data interfaces, able to handle a variety of electric propulsion systems, thanks to the ability to regulate and distribute electric power, to exchange data according to several protocols, and to provide different mechanical layouts. The test platform is ready to start the first verification campaign. The paper describes the detailed design of the platform and the main results of the AIV activities.

• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.3
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• pp.37-53
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• 2016

This paper deals with an optimal output control for Space Shuttle Main Engine (SSME), a liquid propellant rocket engine using a staged-combustion cycle. For this purpose, we modeled simplified mathematical model of SSME using each SSME component divided into 7 major categories and found trim points called Rated Propulsion Level (RPL). For design the closed-loop system of SSME, we designed optimal output feedback Linear Quadratic Regulation (LQR) control system using SSME linearized model under RPL 104% and demonstrated the performance of the controller through numerical simulation.

• Journal of Aerospace System Engineering
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• v.18 no.2
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• pp.95-103
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• 2024

The propulsion technology used in unmanned Aerial Vehicles (UAVs)—which represent one of the most important development directions in aviation—is significantly related to their flight performance. This review paper discusses the different types of propulsion technologies used in unmanned aerial vehicles, namely the internal combustion engine (reciprocating, rotary, and gas turbine engines), the hybrid system, and the pure electric system. In particular, this paper presents and discusses the classification, working principles, characteristics, and critical technologies of these types of propulsion systems. These findings are expected to be helpful in establishing a development framework, comprehensive views, and multiple comparisons of future UAV propulsion systems.

• Journal of Aerospace System Engineering
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• v.10 no.3
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• pp.23-31
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• 2016

The intermediate mixing chamber is one of various methods for improving the regression rate and combustion efficiency of the hybrid rocket. The mixing chamber with its non-combustible material makes the propulsion performance increase, but it leads to a low fuel-loading density in the combustion chamber; therefore, this performance-related trade-off between the mixing chamber and the low fuel-loading density was studied. In this study, the trade-off was conducted by comparing the intermediate-mixing-chamber case with a w/o-mixing-chamber case. The small hybrid-sounding rocket is designed with internal ballistics for comparing the rocket length to the weight. In addition, an external ballistic analysis was conducted for comparing the performances of the w/- and w/o-mixing-chamber cases. As a result, the intermediate-mixing-chamber case shows that the length and the weight were decreased to 12 % and 8 %, respectively; furthermore, when compared with the normal cases, the estimated altitude result of the w/-mixing-chamber case was increased to approximately 75 m.

• Current Industrial and Technological Trends in Aerospace
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• v.7 no.1
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• pp.43-55
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• 2009

Advanced countries in aerospace have been struggle to realize the hypersonic air-breathing system since originating the concept of the hypersonic air-breathing propulsion system during the first half of the twentieth century. At last, NASA's X-43A Hyper-X did successful Mach 10 flight in November 2004. Each countries are running the program to applicate this hypersonic air-breathing propulsion system to SSTO(Single Stage to Orbit) or TSTO(Two Stage to Orbit) vehicle or hypersonic missile system at present. In this paper, we wrote the history and current issues of the hypersonic air-breathing propulsion system and hypersonic flight with the hypersonic air-breathing propulsion system.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.2
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• pp.87-94
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• 2019

Liquid rocket propulsion test facility should provide for the interface condition installed on the upper level system for the test article. In addition, safety provision should be provided to be ready for accident such as explosion which can be occurred during development stage. For this purpose infra-structures of test facilities must be constructed so that stable combustion test can be performed and be guard against accidents. In this article, various aspects for infrastructures of propulsion test facilities are investigated including architecture and civil engineering aspects, test stand, room arrangements, interfaces among facilities, fire-fighting facilities, electrical power facilities.