• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.10a
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• pp.257-260
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• 2010

실제 규모 ISO 9705 표준 화재실에서 액체연료를 대상으로 연소효율 개념에 관한 실험적 연구가 수행되었다. 특히 구획 외부에서 측정되는 총괄연소효율과 구획 내부의 고온 상층부에서 측정된 국부연소효율 개념을 비교 검토하였다. 주요 결과로서, 총괄연소효율은 총괄당량비 증가에 따라 비교적 선형적인 감소경향을 보였다. 반면에 국부연소효율은 총괄당량비가 증가함에 따라 2차 곡선의 형태로 크게 감소됨을 확인하였다. 위 결과를 통해 국부연소 효율에 대한 정보는 구획 내부의 화재현상을 이해하는데 유용한 변수임을 알 수 있었다. 또한 국부연소효율은 구획화재의 상사과정에서 중요한 변수로 사용될 수 있음을 논의하였다.

• 전기의세계
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• v.31 no.3
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• pp.187-190
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• 1982

발전효율은 증기발생용 수질 보일러의 구조 및 재질 등 여러가지가 있겠으나 그중 연료의 연소효율이 가장 중요하여 이것과 관련한 성상 및 연료현상에 대하여 기술하고 또한 국내에서는 이를 성능시험에 대한 제도적 장치 및 기법이 확립되어 있지 않아 성능 기준의 판정이 곤란한 실정이므로 측정 방법도 간단히 부연하였다.

• Journal of the korean Society of Automotive Engineers
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• v.9 no.4
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• pp.23-34
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• 1987

연소 기관용 연료의 효율적 이용과 연소 효율 향상을 위한 연소 기술의 개발에 더욱 노력을 경주 하여야 한다. 이러한 관점에서 연소 기술의 개발과 더불어 새로운 대체연료에 관한 연구가 더욱 활발히 이루어 져야 할 것으로 생각된다. 그러므로 여기서는 대체 연료로 기대되는 석탄액화유, 알코올연료, 태양에너지 중에서 연소 기관용 연료로 주목되고 있는 알코올연료의 특성과 연소 기관의 적용성과 그 문제점에 대하여 살펴 보기로 한다.

• Fire Science and Engineering
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• v.24 no.6
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• pp.145-152
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• 2010

A study on combustion efficiency concept was conducted for the under-ventilated fires in a fullscale ISO 9705 room. In particular, a comparison between global combustion efficiency (CE) measured outside the compartment and local CE measured at upper layer inside the compartment was focused. Heptane, toluene and iso-propanol were used to consider the wide ranges of heat of combustion and soot yield. As a result, the global CE was decreased linearly with increasing in global equivalence ratio (GER). On the other hand, the decreasing rate of local CE was increased gradually with increasing in GER. From these results, it was known that the information on local CE was very useful parameter to understand the fire phenomena inside the compartment. In addition, it was discussed that the local CE might be used as an important parameter in the process of scaling for the compartment fires.

• Journal of the Korean Society of Propulsion Engineers
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• v.3 no.3
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• pp.31-39
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• 1999

In this paper, numerical experiment is attempted to analyze and compare the combustion efficiency of the burning sprays due to OFO, FOF triplet / FOOF split doublet injectors. Preconditioned Wavier-Stokes equation system with low Reynolds number $\kappa$-$\varepsilon$ model for turbulence closure, is LU-SGS time-integrated. Spray processes are modeled by DSF analysis with experimentally determined injection characteristics. n-heptane/air global reaction model approximates the combustion for simplicity, and the influence of turbulence on the chemical reaction is included using eddy dissipation model. The results showed the FOF triplet injector of highest combustion efficiency, whereas the OFO type of poet performance. It was also observed that the droplet mean diameter and the average gas temperature due to the mixing efficiency, are the representative parameters for the performance design of combustion.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.6
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• pp.53-61
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• 2022

The estimation method of combustion efficiency has been introduced by using closed bomb test(CBT). The Noble-Abel equation of state was applied to consider the real gas effects to take account of high operation pressure about a couple of 100 atm. of CBT. The heat loss through the CBT wall was considered. The volume change of grain was calculated by applying form functions, which estimated combustion efficiency of 8 different gain shapes. The combustion estimation method proposed in this study was fairly validated by the comparision with the pressure-time history data of the CBT experiments. The effects of both grain shape and propellant loading density were analyzed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.2
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• pp.192-203
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• 1990

여러 가지 다른 형태의 노즐을 공기 선회식 버너와 공기의 선회가 없는 버너(CB-125 Burner)에 장치하여 공기 분사식으로 오일을 분사하여 연소로에서 연소시켰다. 연소로는 길이 3m에 약 1m 상(3) 의 연소공간을 가졌으며 상부에는 열전대를 장치하고 하부에는 물이 흐르는 관을 설치하여 열효율을 계산할 수 있게 설계하였다. 연소로 연돌부에는 CO 하(2), CO, O 하(2) 가스 분석기를 사용하여 과잉공기량과 고온계로 배기가스 온도를 측정하도록 하였다. 모든 측정치는 연소곡선과 효율곡선에 의하여 얻어진 상수를 이용하여 계산한 연소로 성능방정식에 의하여 평가하였다. 실험치에 의해 계산한 벽면 열손실량과 열전달 공식에 의해 산출한 열손실량을 비교 분석하여 측정치의 정확도를 추정하고 과잉공기의 효과도 검토하였다. 그 결과 본 연구에서 사용된 두 종류의 버너와 여러 형태의 노즐이 오일 연소시 열효율 면에서 큰 차이를 보이지 않고 있음을 알았다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.460-468
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• 2021

This study investigated the enhanced combustion efficiency of an "air-cooled combustion system" with single F.D. fan, and performed a numerical analysis for the operation and design conditions to increase the combustion efficiency. The combustion efficiency in an actual combustor was compared before and after the structure modification. Numerical analysis for application of a single fan revealed the difficulty of forming a turbulence for circular combustion conditions. This is because the supply ratio of combustion air supplied into 2 flow paths becomes irregular in the combustion furnace due to a change in friction force and pressure in each flow path. Subsequently, two methods of supplying air into the combustion furnace were analyzed numerically to obtain the optimal combustion conditions of an air-cooled combustion system. The first method involved injecting the preheated combustion air after a 180~360 degree rotation from the outer wall, whereas in the second method, the combustion air was injected into the combustion furnace in a tangential direction after primary heat exchange outside the combustion furnace, by applying a rotatable vane structure in the combustion furnace. Results reveal that application of a single F.D. fan to the air injection into a rotatable combustion furnace is desirable for optimization of the combustion conditions for applying a duct structure having a dual cooling wall for the cooling of the outer wall of the combustion furnace, and for maintaining perfect mixing in the combustion furnace. We therefore confirmed enhanced combustion efficiency by comparing the actual combustion efficiency before and after structure modification.

• Journal of the Korean Society of Propulsion Engineers
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• v.8 no.2
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• pp.95-101
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• 2004

An experimental investigation was conducted to investigate the effects of the equivalence ratio and air mass flux on the combustion efficiency in a solid fuel ramjet used fuel grains which were highly loaded with boron carbide. Combustion efficiency increased with increasing equivalence ratio (grain length), and decreasing air mass flux. Higher inlet air temperature produced higher combustion efficiencies, apparently the result of enhanced combustion of the larger boron particles those burn in a diffusion controlled regime. Short grains which considered primarily of the recirculation region produced larger particles and lower combustion efficiencies. The result of the normalized combustion efficiency increased with inlet air temperatures coincident with the result of the Brayton cycle thermal and the total efficiency relating to the heat input.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.05a
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• pp.573-578
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• 2003

본 논문은 산업체에서 발생하는 휘발성 유기물질을 연소하는 직접연소기술에 선회연소 개념을 접목하여 개발된 Cyclonic recuperative thermal oxidation system의 연소성능 실험 결과이다. 기존의 recuperative system의 열효율이 75%로 regenerative thermal oxidation보다 낮아 운전비가 많이 소요되는 단점을 극복하기 위해 기존의 연소실에 cyclone 연소시스템을 적용하여 고효율화 시키고자 하는 것이 핵심이다.(중략)