• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1999.04a
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• pp.4-4
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• 1999

최근 충남대에서는 다양한 추진제와 연소 조건으로 액체로켓 연소 실험이 진행되고 있으며 그에 비례하여 많은 사고들이 발생하고 있다. 한 예로 GO$_2$/kerosene을 추진제로 하는 노즐삭마 시험용 로켓엔진(추력 1001bf, 연소실 압력 600psia) 개발 중에 화염이 인젝터면에 형성되어 인젝터면을 손상시키는 사고를 여러 번 경험하게 되었다. 본 연구는 인젝터 손상의 원인을 규명하여 안정적인 인젝터 설계에 도움을 주기 위한 목적으로 실험용 동축 인젝터를 제작하여 화염 부상 특성을 실험적으로 연구하였다. 사용된 인젝터는 연료인 Kerosene을 접선형 선회기로부터 90$^{\circ}$의 원뿔 각을 가지고 분무되도록 설계하였으며, 그 주위로 산하제인 GO$_2$가 연소실의 축방향에 수평하게 분무되도록 설계하였다. 2-유체 동축 인젝터의 난류 확산 화염에서 연료와 산화제의 혼합은 화염 특성을 결정하는 주요 변수이므로 인젝터로부터 분무되는 추진제간의 유량을 변화시켜 화염 부상 특성을 연구하였다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2002.04a
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• pp.6-7
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• 2002

동축형 인젝터는 이미 여러 발사체에서 널리 쓰이고 있는 인젝터의 한 형태로서 또 다른 인젝터 방식인 충돌형과 비교하여 구조가 복잡한 단점이 있는 반면에 연소 현상의 불안정성에 대해 덜 민감하며 미립화와 혼합의 특성도 우수하다. 이런 동축형 인젝터는 크게 스월 방식과 shear 방식으로 나누어진다. 이중에서 스월 인젝터는 산화제와 연료의 유입구에 접선 방향의 속도를 줌으로써 conical sheet 형태의 분무장을 형성하여 미립화와 혼합을 꾀하는 방식이다. 이와 같은 스월 인젝터에서 중요한 변수 중에 하나인 recess의 변화에 대해 분무 형상과 미립화 혼합특성까지 파악해보았다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.147-150
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• 2006

The influences of injection conditions and recess configuration of liquid-liquid swirl coaxial injector on spray characteristics were investigated. The characteristics of the coaxial spray in internal mixing injection region were mai y controlled by the merging phenomenon and momentum balance between two liquid sheets, but those in internal mixing injection region were influenced by the impingement phenomenon as well as momentum balance between two liquid sheets.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.3
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• pp.1-8
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• 2006

The influences of injection conditions and recess configuration of liquid-liquid swirl coaxial injectors on spray characteristics were investigated. The characteristics of the coaxial spray in internal mixing injection region were mainly controlled by the merging phenomenon and momentum balance between two liquid sheets, but those in internal mixing injection region were influenced by the impingement phenomenon as well as momentum balance between two liquid sheets.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.577-580
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• 2010

Coaxial injectors using GCH4/LOx as propellants was designed with shear(gas)/shear(liquid) type and shear(gas)/swirl(liquid) type. Spray characteristics were investigated by cold flow test. Spray patterns of the shear/shear and the shear/swirl type injectors were like a spout of water and hollow cone, respectively. Atomization efficiency of the shear/swirl type injector was better than atomization efficiency of the shear/shear type injector.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.322-326
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• 2005

The spray and acoustic characteristics of a swirl coaxial injector are studied experimentally. The spray and acoustic characteristics of a swirl coaxial injector are investigated according to the injection conditions, such as the pressure drop of the liquid and gas phase, and injector geometries, such as recess length and gap size between the inner and outer injector.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.217-220
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• 2009

This paper presents experimental results of Recess Characteristic of Swirl Coaxial Injector of fuel-rich gas generators. It was revealed that the internal impinging phenomenon played an important role in the spray characteristics, such as spray angle and breakup length.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.29-33
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• 2010

This study aim to investigate the internal flow characteristics by recess length of swirl coaxial injector for gas generator has propellant of Kerosene-LOx. Recess length is a very important element, have influence in spray stability and LOx post damage. The influence of recess length was analyzed by visualizing internal flow and measuring liquid film thickness and manifold pressures. Also, each spray characteristic by recess length was investigated in internal or external injector.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1999.10a
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• pp.1-1
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• 1999

2유체 동축인젝터(coaxial twin fluid injector)는 액체산소와 액체수소를 추진제로 사용하는 SSME(Space Shuttle Main Engine)이나 유럽의 Arian 5 Vulcain 엔진과 같은 저온추진제 엔진에 널리 사용되고 있다. 추진제를 미립화 시키는 장치로서 사용하는 다른 여러 형태의 인젝터에 비교할 때 저속의 액체산화제 주위에 고속의 가스연료가 분사됨으로서 발생되는 전단력에 의해 추진제가 미립화되는 특징을 가지며, 이러한 메카니즘은 매우 복잡하여 아직까지 정확히 규명되지 못하고 있는 실정이다.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.1
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• pp.1-8
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• 2019

To analyze the dynamic behavior and the structure of the gaseous methane-gaseous oxygen diffusion flame formed by a swirl/shear-coaxial injector, combustion experiments were carried out under different propellant injection conditions. As a result, the OH radical emission intensity of the diffusion flame visualized through chemiluminescence was observed to increase as the propellant mass flow and the momentum flux ratio increased. And flames with swirl showed a more high radical emission intensity than those without swirl.