• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.2
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• pp.47-59
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• 2022

Liquid hydrogen/liquid oxygen rocket engines with highest specific impulse have been developed since the 1950s and used until now to maximize the capability of space launch vehicles. Domestic liquid hydrogen infrastructures for the production, transportation and distribution are being expanded at world-class level with the rise of hydrogen economy, which is a great opportunity for the performance enhancement for indigenous space launch vehicles. In this paper, feasibility of applying liquid hydrogen as a propellant is investigated in various aspects. The status of domestic liquid hydrogen infrastructure, the technologies required for liquid hydrogen engines, and operational aspects for safe handling of hydrogen are reviewed. In addition, test facilities for developing hydrogen engines are introduced briefly.

• Journal of the Korean Society of Propulsion Engineers
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• v.8 no.2
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• pp.32-38
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• 2004

A comprehensive understanding is given for the hot-firing test results, which were obtained throughout the verification program of mono-propellant hydrazine rocket engines (thrusters) producing 0.95 lbf (4.2 N) of nominal steady-state thrust at an inlet pressure of 350 psia (2.41 Mpa). A scrutiny for the engine performance is made in terms of thrust and temperature behavior of steady state firing mode at the given propellant injection pressures: Pinj = 400, 250, 100, and 50 psi. The thrust and specific impulse are compared with a reference performance of 1-lbf standard rocket engines and their normalization procedure is introduced. A practical engineering approach to the data measurement and reduction is addressed, too.

• Current Industrial and Technological Trends in Aerospace
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• v.8 no.2
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• pp.86-97
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• 2010

This paper treats with the history and current trends in the developments of liquid-propellant rocket engine in Russia and Ukraine which are among world leaders in the technology of liquid rocket engine(LRE). In 1960s formerly the Soviet Union accepted the closed cycle engine for increasing the pressure in the combustion chamber and specific impulse to the maximum. However, since financially difficult times after 1990, they have decreased the cost for the development of new rocket engines. It was achieved by using existing units for new developed engines and minimizing the total number of engines and tests through the reasonable planning in the process for the experimental improvement of LRE. In addition, nowadays international cooperation in supplying LRE for commercial rocket and development of next generation LRE, such as 3 components engines and mathane engines, are proceeding.

• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.4
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• pp.46-58
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• 2010

Hydrogen peroxide(HP) and liquid methane have deserved renewed considerations as green propellants in recent years, because main design concerns in the development of the new generation propulsion system for spacecrafts are concentrated on low operation cost and environmental cleanness. Although HP has a long history of application to aerospace propulsion systems due to high density, mono-propellant characteristics and low toxicity, it had been replaced by hydrazine and liquid oxygen due to extreme performance requirement during the cold war. But HP has received a renewed interest due to its increased stability and many researches have been conducted to develop high performance LREs(Liquid Rocket Engines) using HP. Liquid methane has also received a new interest in rocket propulsion system for the future space exploration according to its possibility of ISRU(In-Situ Resource Utilization).

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.5
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• pp.563-569
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• 2012

An energy balance analysis is conducted for a 30 t thrust level liquid rocket engine. The relations between thrust and combustion pressure, between thrust and propellant flow rate, and between combustion pressure and fuel pump pressure rise are compared against those indicated by a published database of the existing rocket engines. A combustion pressure higher than the old design value is obtained, implying that the present design is high-performance oriented. The thrust to propellant flow rate ratio is the same as that of the existing engines, indicating that the specific impulse performance is at the usual level. The fuel pump pressure rise is found to be slightly high when the combustion pressure is considered, and it is attributed to the pressure budget of the present ground test engine not being optimized.

• International Journal of Aeronautical and Space Sciences
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• v.17 no.4
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• pp.535-550
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• 2016

Securing the safety and the reliability of liquid-propellant rocket engines (LREs) for space vehicles is indispensable as engines consist of many complex components and operate under extremely high energy-dense conditions. Thus, health monitoring has become a mandatory requirement, especially for the reusable LREs that are currently being developed. In this context, a dynamic simulation program based on MATLAB/Simulink was developed in the current research on the Space Shuttle Main Engine (SSME), a partly reusable engine. Then, a series of fault simulations using this program was conducted: at a steady state operating condition (104% Rated Propulsion Level), various simulated fault conditions were artificially injected into the simulation models for the five major valves, the pumps, and the turbines of the SSME. The consequent effects due to each fault were analyzed based on the time responses of the major parameters of the engine. It is believed that this research topic is an essential pre-step for the development of fault detection and diagnosis algorithms for reusable engines in the future.

• Journal of ILASS-Korea
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• v.25 no.3
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• pp.126-131
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• 2020

Throttleable rocket engines are in high demand due to the diversification of space missions. Pintle injector is known to be suitable for throttleable rocket engines, because of its high efficiency in overall thrust zone. In this study, the relationship between spray angle of a throttleable pintle injector and total momentum ratio based on hot fire test conditions was investigated. As a result, the spray angle in 100% and 60% throttling level is higher than the spray angle obtained by the case which considers only propellant mass flow rate, owing to higher total momentum ratio (TMR). The results of this study may be useful for predicting spray angle in hot fire test.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.238-238
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• 2012

Report is devoted to place and role of numerical simulation in design of rocket propulsion systems. In introduction advanced solutions in liquid propellant rocket engines design are presented. Further essence of design process described briefly. The central place of method of solution of direct problem in design process was shown. Numerical simulation for solving direct problem of fluid dynamic was used as the alternative to theoretical and experimental approaches. Main features of numerical models of processes in propulsion systems were observed. Some results of simulation and (or) design of different types of chemical propulsion system were presented also. The combined rocket engine, rocket engine with injection of after-turbine gas into supersonic part of the nozzle, solid propellant engine and hybrid propulsion engine are under consideration.

• 한국연소학회:학술대회논문집
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• 2012.11a
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• pp.33-35
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• 2012

This study has been mainly motivated to numerically model the supercritical mixing and combustion processes encountered in the liquid propellant rocket engines. In the present approach, turbulence is represented by the extended k-e model. To account for the real fluid effects, the propellant mixture properties are calculated by using generalized cubic equation of state. In order to realistically represent the turbulence-chemistry interaction in the turbulent nonpremixed flames, the flamelet approach based on the real fluid flamelet library has been adopted. Based on numerical results, the detailed discussions are made for the effects of swirl number on flame structure of supercritical kerosene/LOx double swirl coaxial injector.

• 한국연소학회:학술대회논문집
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• 2013.06a
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• pp.81-82
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• 2013

This study has been mainly motivated to numerically model the supercritical mixing and combustion processes encountered in the liquid propellant rocket engines. In the present approach, turbulence is represented by the standard k-e model. To account for the real fluid effects, the propellant mixture properties are calculated by using generalized cubic equation of state. In order to realistically represent the turbulence-chemistry interaction in the turbulent nonpremixed flames, the flamelet approach based on the real fluid flamelet library has been adopted. Based on numerical results, the detailed discussions are made for the effects of swirl on flame structure of supercritical kerosene liquid propellant combustion.