• 한국연소학회:학술대회논문집
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• 한국연소학회 2004년도 제29회 KOSCI SYMPOSIUM 논문집
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• pp.244-249
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• 2004

Experiments were performed to investigate the characteristics of combustion of 7MW-3 air stages combustion system for a heavy oil firing boiler. Several fuel nozzles were developed for the purpose of lowering pollutions in another institute and ${\Phi}$-jet nozzle among them was equipped to the combustion system. A variety of combustion phenomena were observed as air stage ratio, air fuel ratio and load are changed for each nozzle. Main combustion characteristics are shape of flame, NOx and CO generations, smoke scale number. Through lots of adjustments, the combustion system reaches such goals as the low NOx of 160 ppm, CO of 300 ppm corrected at $O_2$ of 4% and dust of 150 mg/Sm3.

• 한국연소학회지
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• 제7권1호
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• pp.58-64
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• 2002

The bed combustion in an incinerator interacts with the gas flow region through heat and mass transfer. Combined bed combustion and gas flow simulations are performed to investigate this coupled interaction for various operating conditions and furnace configurations. Radiation onto the bed from the furnace is interrelated with the combustion characteristics in the bed, and is also affected by the flow pattern in the gas flow region. Since the contribution of gaseous emission to the total radiation is significant, an adequate flow pattern in a well-designed furnace shape would lead to an increased heat influx on the bed, especially in the early stage of the waste combustion. Advancing the initiation point of the waste combustion can also reduce the size of the lower gas temperature region above the bed, which can be achieved by controlling operating conditions such as the waste feeding rate, the bed height and the primary air flow distribution.

• 한국자동차공학회논문집
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• 제11권4호
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• pp.29-36
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• 2003

A cylindrical constant volume combustion chamber was used to investigate the flow characteristics at spark plug and the combustion characteristics of inhomogeneous charge methane-air mixture under several parameters. The flow characteristics such as mean velocity and turbulence intensity was analyzed by hot wire anemometer. Combustion pressure development measured by piezoelectric pressure transducer was used to investigate the effect of initial charge pressure, excess air ratio and ignition times on combustion pressure and combustion duration. Mean velocity and turbulence intensity had the maximum value at 200 or 300ms and then decreased to beneath 0.05m/s gradually at 3 seconds. Second mixture is accompanied by an increase in the combustion rate, and that the higher the mass which is added in the second stage injection, the faster the burn rate.

• Journal of Mechanical Science and Technology
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• 제18권6호
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• pp.1010-1018
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• 2004

This study presents the methodological aspects of combustion instability modeling and provides the numerical results of the model (sub-scale) combustion chamber, regarding geometrical dimensions and operating conditions, which are for determining the combustion stability boundaries using the model chamber. An approach to determine the stability limits and acoustic characteristics of injectors is described intensively. Procedures for extrapolation of the model operating parameters to the actual conditions are presented, which allow the hot-fire test data to be presented by parameters of the combustion chamber pressure and mixture (oxidizer/fuel) ratio, which are customary for designers. Tests with the model chamber, based on the suggested scaling method, are far more cost-effective than with the actual (full-scale) chamber and useful for injector screening at the initial stage of the combustor development in a viewpoint of combustion instabilities.

• Journal of Advanced Marine Engineering and Technology
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• 제23권3호
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• pp.300-310
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• 1999

A constant-volume combustion chamber is developed to measure the burnt gas temperature over the wide ranges of equivalence ratio from 1.5 to 2.7 and pressure from 0.1 to 2.7 and pressure from 0.1 to 6 MPa by two-color method. The combustion temperature is also calculated by the conventional two-region model. The premixed fuel rich propane-oxygen-inert gas mixtures under high pressures are simultaneously ignited by eight spark plugs located on the circumference of combustion chamber with 45 degree intervals. The eight converging flames compress the end gases to high pressures. The transmissiv-ity in the chamber center during the final stage of combustion at the highest pressure is measured by in situ laser extinction method. Comparisons are made with the combustion temperatures between two-color method and two-region model. It is found that the burnt gas temperature mea-sured by two-color method is higher than that calculated by two-region model because of being the negative temperature gradient on the calculation and the temperature distribution of light path-length on the measurement and the burnt gas temperature for the turbulent combustion is higher than that of the laminar combustion under the same conditions because the heat loss for turbulent combustion is lower due to the shorter combustion period.

• 한국유체기계학회 논문집
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• 제18권6호
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• pp.31-36
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• 2015

A multi-stage turbocharger system has been constructed for HALE UAV internal combustion engine. To boost rarefied intake air up to sea level condition, the turbocharger system should consist of 3 stages including heat exchanger located after compressor outlet to drop compressed air temperature. One dimensional system analysis has been conducted by matching required power between compressor and turbine and adequate turbochargers have been searched for from commercially available models targeting for automobiles. By applying commercial automobile turbochargers to the multi-stage turbocharger system, it is expected that considerable amount of research resources will be saved.

• 한국추진공학회지
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• 제16권6호
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• pp.92-97
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• 2012

발사체의 추진기관은 일반적으로 산화제와 연료를 연소실로 공급하여 추진력을 얻게 된다. 개발 중에 있는 한국형 발사체(KSLV-II) 2단 엔진의 경우 산화제로는 액체산소(Liquid Oxygen)를 사용하고 연료로는 JET-A1이 사용될 예정이다. 터보펌프 공급방식인 2단 엔진의 주요 구성은 연소기와 터보펌프, 엔진공급시스템 등으로 구성되어 있다. 액체 추진 엔진 개발을 위해서는 서브시스템인 연소기 개발이 선행되어야 하고 설계 및 제작된 연소기의 성능 검증은 연소기 연소시험설비(CCTF)에서 수행된다. 우주센터에 구축 예정인 연소기 연소시험설비에 대한 상세설계가 수행되었으며, 본 설계 결과를 기준으로 AMESim을 사용하여 산화제공급시스템에 대한 모델링을 수행하여 산화제 공급특성을 해석하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.502-506
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• 2012

발사체의 추진기관은 일반적으로 산화제와 연료를 연소실로 공급하여 추진력을 얻게 된다. 개발 중에 있는 한국형 발사체(KSLV-II) 2단 엔진의 경우 산화제로는 액체산소(Liquid Oxygen)를 사용하고 연료로는 JET-A1이 사용될 예정이다. 터보펌프 공급방식인 2단 엔진의 주요 구성은 연소기와 터보펌프, 엔진공급시스템 등으로 구성되어 있다. 액체 추진 엔진 개발을 위해서는 서브시스템인 연소기 개발이 선행되어야 하고 설계 및 제작된 연소기의 성능 검증은 연소기 연소시험설비(CCTF)에서 수행된다. 우주센터에 구축 예정인 연소기 연소시험설비에 대한 상세설계가 수행되었으며, 본 설계 결과를 기준으로 AMESim을 사용하여 산화제공급시스템에 대한 모델링을 수행하여 산화제 공급특성을 해석하였다.

• 한국추진공학회지
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• 제16권4호
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• pp.87-92
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• 2012

우주발사체 추진기관은 일반적으로 산화제와 연료를 연소실로 공급하여 추진력을 얻게 된다. 개발중에 있는 한국형 발사체(KSLV-II) 2단 엔진의 경우 산화제로는 액체산소(Liquid Oxygen)를 사용하고 연료로는 JET-A1이 사용될 예정이다. 터보펌프 공급방식인 2단 엔진의 주요 구성은 연소기와 터보펌프, 엔진공급시스템 등으로 구성되어 있다. 액체 추진 엔진 개발을 위해서는 서브시스템인 연소기 개발이 선행되어야 하고 설계 및 제작된 연소기의 성능 검증은 연소기 연소시험설비(CCTF)에서 수행된다. 우주센터에 구축 예정인 연소기 연소시험설비에 대한 상세설계가 수행되었으며, 본 설계 결과를 기준으로 AMESim을 사용하여 연료공급시스템에 대한 모델링을 수행하여 연료 공급특성을 해석하였다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제33회 KOSCO SYMPOSIUM 논문집
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• pp.42-45
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• 2006

A new and reusable energy source is water-treatment sludges. There is a significant need for understanding the characteristics of sludge combustion related to improving efficiency and ensuring the safety of this new energy source. Because sludges are composed of solids and gas mixture, the combustion of the mixture may become quite complex. Not only decomposition of conventional organic elements but also dust explosion may be important during the process of converting sludges into a new and safe form of energy. Sludge combustion mainly involves hydrogen, methane, hydro carbons, carbon, and organic particles. Dust explosion during the gasification stage may depend on the surrounding temperature and the composition of gases. The uncertainty in the explosive behavior of energetic source is noted in this work. We study the explosion characteristics of sludge combustion while the reusability of sewage sludges as a new form of energy is also investigated.