• 에너지공학
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• 제13권2호
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• pp.112-117
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• 2004

휘발성 유기물질은 도장공정, 염색, 건조공정 등 화학공정에서 발생하는 저발열량 가스이다 VOCs의 특징은 발열량이 150kcal/㎥ 이하이며 착화를 위한 활성화 에너지가 높고 발생 에너지가 낮다는 것이다. 따라서 연소 안정성은 낮아지고 처리공정은 고에너지 소비공정이 된다. Cyclone연소시스템은 연소기 내에 강한 선회 유동을 만들어서 에너지를 순환시켜 활성화에너지를 낮추어주고 열밀도가 높아 일반적인 swirl 연소 시스템에 비해 고온의 연소온도를 유지할 수 있으며 혼합성을 향상시킨다 본 논문에서는 휘발성 유기물질의 열산화를 위해 최적의 cyclone 연소시스템을 개발하는 것을 목적으로 수행되었으며 특별히 설계된 연소기에서 연소온도와 배가스 조성에 미치는 swirl number의 영향을 정립하였다.

• 대한기계학회논문집B
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• 제27권11호
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• pp.1587-1594
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• 2003

Increased energy costs have placed demands for improved combustion efficiency, high equipment availability, low maintenance and safe operation. Furthermore low NO$_x\$ modification, installed due to strict environmental legislation, requires very careful combustion management. The flame monitoring system has been developed specially to satisfy these requirements. We aimed at gaining the relationship between the burner flame image and emissions such as NO$_x$ and unburned carbon in furnace by utilizing the image processing method. For the first step of development, its possibility test was undertaken with bench furnace. The test proceeded to the second step with pilot furnace and the system was observed to be effective for evaluating the combustion conditions. By using this technology, it is possible to perform continuous monitoring of the combustion conditions and instant detection of individual changes for each burner to prevent future loss of ignition. This may contribute to the saving of burner adjusting times for the changes of loads and fuels and to the reduction of the slagging as well.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제32회 KOSCO SYMPOSIUM 논문집
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• pp.69-74
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• 2006

An Experimental study was conducted on $CO_2$ recycle combustion heating system using pure oxygen instead of conventional air as an oxidant, which is thereby producing a flue gas of mostly $CO_2$ and water vapor($H_2O$) and resulting in higher $CO_2$ concentration. The advantages of the system are not only the ability to control high temperatures characteristic of oxygen combustion with recycling $CO_2$. but also the possibility to reduce NOx emission in the flue gas. A small scale industrial reheating furnace simulator and specially designed variable flame burner were used to characterize the $CO_2$ recycle oxy-fuel combustion, such as the variations of furnace pressure, temperature and composition in the flue gas during recycle. It was found that $CO_2$ concentration in the flue gas was about 80% without $CO_2$ recycle, but increased to $90{\sim}95%$ with $CO_2$ recycle. The furnace temperature and pressure was decreased due to recycle and the NOx emission was also reduced to maintain under 100ppm.

• 설비공학논문집
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• 제20권9호
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• pp.581-589
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• 2008

The pulverized coal combustion behavior in the utility boiler is very complex since so many physical and chemical processes happen in it, simultaneously. The mixing of pulverized coal with combustion air plays an important role in achieving the efficient combustion and stable boiler operation. The distribution of combustion air supplied to the furnace through the windbox damper system has not been clearly known since the individual measurements of air flow for each air nozzle were not possible, yet. The present study describes the CFD modelling of windbox damper system and aims to obtain the air flow rates and pressure loss coefficients across the present five damper systems, respectively. The one dimensional flow network model has been also established to get air flow distributions across the windbox damper, and applied to the actual plant operation condition. Compared with the designed air flow distribution, the modelled one gives a reasonable agreement. For the actual plant operation, the predicted air flow distribution at each air nozzle is differed with the designed data and strongly affected by the individual opening angle.

• 한국전산유체공학회지
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• 제16권3호
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• pp.88-94
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• 2011

The availability of the thermal energy has been deeply recognized recently to encourage the cascade usage of thermal energy from combustion. Within the framework, a 1 kW class Stirling engine based cogeneration system has been proposed for a unit of a distributed energy system. The capacity has been designed to be adequate for the domestic usage, which requires high compactness as well as low emission and noise. To develop a highly efficient system with satisfying these requirements, a premixed slot type short flame burner has been proposed and a series of numerical simulation has been performed to establish a design tool for the combustion chamber. The thermal radiation model has been found to highly affect the computational results and a proper resolution to analyze the heat transfer characteristics of the high temperature heat exchanger. Finally, the combustion characteristics of the premixed flame with the metal fiber type burner has been studied.

• 한국추진공학회지
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• 제8권4호
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• pp.91-101
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• 2004

분사기와 연소실만을 가지는 연소기의 수학적 선형모델을 가지고, 액체추진제 로켓엔진 연소기에 대한 저주파 동특성 분석을 수행하였다. 연소실의 압력변화가 추진제 유량변화로 되먹임되는 구조를 가짐에 따라 저주파 섭동을 나타냈으며. 연소실의 시정수가 증가할수록, 분사기의 차압이 증가할수록, 연소시간지연이 짧을수록 시스템은 안정하였다. 분사기 시정수 변화가 안정성에 미치는 영향은 크지 않았다. 연소시간지연이 없는 경우의 시스템은 항상 안정하였으며, 지연시간이 증가할수록 섭동 주파수 및 감쇠율은 줄어들며, 결국 시스템은 불안정하게 되었다.

• 한국자동차공학회논문집
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• 제8권1호
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• pp.23-31
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• 2000

Knock and misfire, kinds of abnormal combustion, are highly undesirable effect on the internal combustion engine. So, it is important to detect these avnormal combuition and control the ignition timing etc. to avoid these mal-effect factors in real engine system. In this study, the system which detects the knock and the misfire using by spark plug is presented. This system is based on the effect of modulation breakdown voltage(BDV) between the spark gaps. The voltage drop between spark plug electrodes, when an electrical breakdown is initiated, depends on the temperature and pressure in combustion chamber. So, we can detect knock and misfire that produce changes in gas temperature and pressure (consequently, its density) using by BDV signal change which carries information about the character of combustion.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2004년도 춘계 학술발표회 논문집
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• pp.197-200
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• 2004

Compared to conventional flame combustion, catalytic combustion had the advantage of oxidation of V.O.C. gas which was high voluminous, low caloric mixture flow. However, the temperature of mixture gas should be over the one of catalytic reaction start and the control of reaction on the catalytic surface tends to be vulnerable. To overcome these obstacles, composition of both catalytic combustor and heat exchanger was devised and named the sequential catalytic combustion system. In this system, only trigger unit needed preheating process for transient starting time. Once trigger unit was ignited, the next unit w3s supplied heat to ignite from that and same process was performed to the last one sequentially. When it come to steady state, whole mixture gas was oxidated at each unit simultaneously and preheating for trigger unit was not needed any more. System of 100 kcalh/hr capacity was devised and operated successfully.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.1019-1024
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• 2008

A 3 MW class oxy-fuel boiler has been developed to capture $CO_2$ from the exhaust gas. The system is a scale-up of the previous 0.5 MW class system in general. A heat exchanger and a mixer are additionally installed to stabilize the flame for the FGR mode. The system yields the exhaust gas with $CO_2$ concentration over 90% and reduced NO emission to 1/10 of conventional air combustion system.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.461-464
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• 2012

한국형발사체 3단에 사용될 7톤급 액체로켓엔진 연소기의 연소시험을 위해 기존 지상연소시험장 고주파 계측 시스템을 개량하였다. 본 논문에서는 개량된 고주파 계측 시스템의 설계 및 주요 기능을 설명하였다.