• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.163-166
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• 2012

The hybrid combustion were performed with the different diaphragm position for the experimental studies on characteristic of regression rate and combustion efficiency. The diaphragm was installed in 25% and 50% of fuel length from the front of solid fuel, respectively. As results of experiments, the position of diaphragm has small effect on the regression rate and combustion efficiency. It is considered that the diaphragm has local effect near the diaphragm.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.3
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• pp.150-156
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• 1975

This paper dealt itself with the relation of the heat release rate with crank angle in combustion process by adjusting the injection time, injection amount and engine speed of diesel engine. The result of test were obtained by analyzing indicator diagram of KUBOTA 2LKE diesel engine, where the indicator was used Tertronix oscilloscope. The combustion period of diesel engine is composed of premixed burning time and combustion controlled time. The larger the premixed burning region, the higher efficiency was obtained with the higher maximum pressure than at the time of the normal smooth operation. The longer the combustion controlled time, the lower the maximum pressure than the period of the normal operation, but the efficiency was decreased. The region of premixed burning was principally controlled by injection delay, but combustion controlled time was affected when oxygen and fuel were mixed. Efficiency of engine was increased at the time of earlier injection time under the constant injection amount, and engine speed, but the pressure increasing was observed higher than the efficiency increasing.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.169-174
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• 2006

This paper is related to a design of high pressure sub-scale combustor with regenerative reeling. As a previous step for the evaluation of thermal heat flux, a similar combustor with cooling water was manufactured. Design conditions with high combustion efficiency and cooling performance were verified through the hot firing tests of the water-cooled high pressure combustor. Finally the regeneratively cooled high pressure combustor has been designed based on these data. After manufacturing it, its practical utility will be tested and verified through hot firing tests.

• Proceedings of the KAIS Fall Conference
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• 2011.05b
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• pp.605-607
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• 2011

자동차의 연료비 절감 대책으로 연소 효율 증대를 위해서 연소실의 와류를 형성시켜주는 장치를 Modeling하여 유동해석을 실시하였다. 와류발생장치가 장착되지 않은 형태의 Model과 와류발생장치의 형태가 다른 Model을 설계하였다. 와류발생장치는 공기의 연소실 흡입 전에 설치되어 와류발생장치의 날개에 의해 흡입공기를 휘감으며 와류를 발생시키게 된다. 본 연구에서는 와류발생자치를 사용함으로써 흡입 공기의 유동과 흡입행정의 압력분포를 해석하여 와류발생장치의 효과를 확인할 수 있다.

• Proceedings of the KAIS Fall Conference
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• 2010.05b
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• pp.1004-1006
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• 2010

차량에 사용되는 무시동 히터 열교환기의 효율 개선을 위하여 열전달 해석을 수행하였다. 연구에 사용된 히터는 연료 공급관을 통해 연소부로 연료를 공급하고 연소시켜, 열교환기에 열을 전달한다. 열전달 효율을 증대시키기 위하여 열전달면 및 연소면의 형상을 해석적으로 개발하였다. 개선된 열교환기 모델은 외부 형상을 기존 제품과 동일하게 설계하여 단품상으로 교체가 가능하도록 설계 하였다. 해석 결과 기존 모델에 대비 개선된 모델에서 열전달 효율이 약 5.6배 향상되었다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.10a
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• pp.259-264
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• 2004

The critical component of combustor having high combustion efficiency for high performance liquid rocket engine is injector. The results of design and hot firing tests of six sub-scale combustors which have respectively an impinging type injector(1ea.), an bi-propellant swirl closed injector(1ea.), and hi-propellant swirl mixed injector(4ea.) were described in this paper. The combustion test were successfully performed. The combustion efficiency have higher value than predicted value and high frequency combustion instability does not occur.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.318-321
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• 2005

The design and performance test of a low NOx gas turbine combustor to be used in 55kW class micro-gasturbine engine was performed in KARI's combustion test facility. The combustor is reverse flow-can type for easy installation of injector and other parts and LNG is used as fuel. The performance targets are $99.5\%$ combustion efficiency, less 10ppm NOx, $30\%$ patten factor and $4\%$ pressure loss. Most of the performances required are satisfied.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.10a
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• pp.157-161
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• 2004

The colse type of engine system, in which the combustion gas after the gas-turbine with high temperature is supplied to the combustion chamber, was selected to increase the energy characteristics in making the rocket engine scheme which makes 1700kN thrust. The nozzle was designed with consideration of film cooling, nozzle efficiency, and the real state of cobmustion gas during the expansion in nozzle. The change of gas state and the composition of the gas through the nozzle was studied by the graphic, too.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.5
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• pp.51-59
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• 2007

The end-burning combustion field using impinging oxidizer injectors are analyzed with tangential type injectors in order to examine their mixing and combustion characteristics. The impinging type showed further improved mixing effect as well as the combustion efficiency compared to the previously studied tangential injector. A novel injector capable of delivering impinging and swirl effect is introduced in this study where it demonstrated that the grain coning effect can be avoided. It was found that the combined impinging and swirling flow would promote the radial mixing rate increasing the residence time and the turbulent intensity. However, the use of the step combustor which may augment the turbulent intensity did not show any notable difference compared to the basic combustor.

• Journal of the Korean Society of Visualization
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• v.3 no.2
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• pp.14-20
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• 2005

내연기관 연소는 난류유동, 분무, 연소, 열전달의 복합적인 현상으로서 열역학적 해석이 주류를 이루어 왔으나 컴퓨터의 발전에 따라 효율 개선과 공해 저감을 목표로 전산유체해석 기법이 적극적으로 도입되고 있다. 내연 기관 연소의 근간을 형성하는 난류 연소 모델링의 기본 개념으로서 가솔린엔진에서의 예혼합연소와 디젤엔진에서의 확산연소에 대한 영역조건평균(zone conditional averaging) 모델과 조건평균닫힘(conditional moment closure) 모델에 대해 설명하였으며 $NO_x$와 soot 예측에 대한 적용과 엔진응용 사례를 소개하였다.