• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제25회 추계학술대회논문집
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• pp.475-478
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• 2005

Ducted 로켓은 가스발생기에서의 1차 불완전 연소반응 및 연소관 내에서의 흡입구로부터 공급되는 공기와의 2차 완전 연소반응을 통해 추력을 발생한다. 로켓의 사정거리는 추진제의 무게, 특히 연료의 무게에 의해 결정되므로 일반적인 고체 추진기관보다 연료효율이 높고 종말속도가 빠르므로 대공, 대함 등의 다양한 추진기관에 적용이 가능할 것으로 기대된다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2004년도 제28회 KOSCO SYMPOSIUM 논문집
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• pp.141-148
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• 2004

Coal combustion in an iron ore sintering bed is a key parameter that determines quality of the sintered ores and productivity of the process. In this study, effects of the different types of coal coke and anthracite - on the combustion in the iron ore sintering bed are investigated by modeling and experiment. Fuel characteristics of coke and anthracite are observed through a few basic analysis and thermo-gravimetric analysis. It was found that coke has a higher reactivity than anthracite due to the difference of surface area and density. Those characteristics are reflected to the 1-D unsteady simulation of the iron ore sintering bed. Calculation results show that different reactivity of the fuel can affect the bed combustion, which implies the further investigation should be performed for obtaining optimal combustion conditions in the sintering bed.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2007년도 제34회 KOSCO SYMPOSIUM 논문집
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• pp.92-97
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• 2007

Numerical simulations were carried out to investigate the base drag characteristics of a base bleed projectile with a central propulsive jet by considering the base burning process. Overall fluid dynamic process is modeled by Navier-Stokes equations for reacting flows with two-equation $k-{\omega}$ SST turbulence closure. The combustion process is modeled by finite-rate chemistry with a given partially burned exit condition of the BBU (base-bleed unit). Besides the demonstrating the capability of the present CFD solver for the base drag and the interaction of the base flow with a rocket plume, present study gives an insight into the fluid dynamics and the combustion process of the hybrid-propulsion projectile.

• 한국연소학회지
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• 제1권1호
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• pp.83-91
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• 1996

A numerical study is carried out to examine the ignition and propagation process of detonation wave in SCRam-accelerator operating in superdetonative mode. The time accurate solution of Reynolds averaged Navier-Stokes equations for chemically reacting flow is obtained by using the fully implicit numerical method and the higher order upwind scheme. As a result, it is clarified that the ignition process has its origin to the hot temperature region caused by shock-boundary layer interaction at the shoulder of projectile. After the ignition, the oblique detonation wave is generated and propagates toward the inlet while constructing complex shock-shock interaction and shock-boundary layer interaction. Finally, a standing oblique detonation wave is formed at the conical ramp.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.301-302
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• 2012

During a last decade, detonative combustion is promising combustion mechanism of high-speed propulsion systems, but is more rigorously considered in these days as a game-changer for the improvement of thermodynamic efficiency of propulsion and power generation systems. Regardless of the skepticism about the pressure loss associated with the strong shock waves, it is shown that the additional compression by the strong shock wave exhibits increased thermodynamics efficiency that is not achievable by conventional compression systems. Present talk will give an introduction to the concepts and the recent activities on the pressure gain combustors (PGC) researches based on detonation phenomena.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년도 제30회 춘계학술대회논문집
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• pp.57-60
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• 2008

고체 추진기관 설계에는 고체 추진제 연소속도, 요구 추력, 연소관 압력, 연소시간, 탄의 직경, 길이, 무게, 최대 가속도와 같은 많은 설계요소 및 제약이 존재한다. 이러한 요소 및 제약의 최적화를 위해 내탄도/외탄도 해석을 위한 통합 설계 프로그램을 개발하였고 고체 로켓 모터의 시험을 통해 그 유용성을 확인하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 제33회 추계학술대회논문집
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• pp.569-572
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• 2009

수소를 연료로 하는 스크램제트 엔진의 수치해석에 비해 탄화수소를 연료로 하는 스크램제트 엔진의 수치해석이 적은 편이었다. 본 논문에서는 탄화수소 계열의 연료 중에 에틸렌을 연료로 하였고, 미공군연구소에 있는 Direct-connect 스크램제트 연소기를 모델로 2차원 수치해석을 수행한다. 에틸렌의 점화 지연 특성을 볼 수 있었고, 모델 스크램제트 내에 연소를 발생시키기 위해 Air throttling을 하였다.

• 한국분무공학회지
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• 제14권2호
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• pp.84-89
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• 2009

In this research, combustion and spray characteristics were investigated experimentally in a constant volume chamber by applying different composition rates of octane number in diesel fuel to a common-rail system. For the visualization, the experiment was carried out under different injection pressures and different cetane number. The test was done by three different types of diesel fuels, the different composition rates of cetane number in diesel fuel and HBD. In summary, this research aims to investigate the combustion characteristics in the application of fuels and compare the results with performance of conventional diesel fuel. This experimental data may provide with fundamentals of the development of diesel engines in future.

• 한국연소학회:학술대회논문집
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• 대한연소학회 2003년도 제27회 KOSCO SYMPOSIUM 논문집
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• pp.159-165
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• 2003

This paper describes numerical efforts to characterize the flame-holding and air-fuel mixing process of model SCRamjet engine combustor, where a hydrogen jet injected into a supersonic cross flow and in a cavity. Combustion phenomena in a model SCRamjet engine, which has been experimentally studied at University of Queensland and Australian National University using a free-piston shock tunnel, was observed around separation region of upstream of the normal injector and inside of cavity. The results show that the separation region and cavity generates several recirculation zones, which increase the fuel-air mixing. Self ignition occurs in the separation-freestream and cavity-freestream interface.

• 한국연소학회:학술대회논문집
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• 대한연소학회 2003년도 제27회 KOSCO SYMPOSIUM 논문집
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• pp.65-74
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• 2003

Air pollution included Nitric Oxide(NOx) from heating boilers is increased by pursuing better life. Development of low NOx emission boiler is strongly needed. However commercial burner for heating boiler is also asked to be thermal efficient and low-cost manufactuable in addition to low NOx emission. Small space for combustor including burner is usually allowed. In this study, parametric study of compact low NOx burner for heating boiler was done using numerical analysis and experiments. Commerical computational fluid dynamic(CFD) program named CFX 5-6 was used for numerical analysis of low NOx burner using turbulent diffusion flame. Comparison of outlet NO and outlet temperature under various equivalence ratio and fuel flow rate was performed between experiment and numerical analysis.