• 한국축산시설환경학회지
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• 제5권2호
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• pp.101-106
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• 1999

This study was conducted to develop a lignite coal heater which can be used to livestock facilities and to test performance of the heater developed. Experimental results are as following: 1. Heating capacity of the heater was 85,000 kcal/h. 2. The concentrations of CO gas in the exhaust gas were the maximum of 759 ppm and the average of 319 ppm; for the concentrations of NOx, the maximum of 212 ppm and the average of 57 ppm ; for the concentrations of SO2 gas, the maximum of 302 ppm and the average of 99 ppm. As the values were less than the allowable concentration limites, they did not violate the air environment law. 3. Problems such as frequent interruption of fuel supply and bridge state were happened. Therefore, it was required that these should be resolved in the future.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.639-646
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• 2000

Hot air heater with light oil combustion is the most common heater for greenhouse heating in the winter season in Korea. However, since the heat efficiency of the heater is about 80%, considerable unused heat in the form of exhaust gas heat discharges to atmosphere. In order to capture this exhaust gas heat a heat recovery system for plant bed heating in the greenhouse was built and tested in the hot air heating system of greenhouse. The system consists of a heat exchanger made of copper pipes, ${\phi}\;12.7{\times}0.7t$ located inside the rectangular column of $330{\times}330{\times}900mm$, a water circulation pump, circulation plastic pipe and a water tame The total heat exchanger area is $1.5m^2$, calculated considering the heat exchange amount between flue gas and water circulated in the copper pipes. The system was attached to the exhaust gas path. The heat recovery system was designed as to even recapture the latent heat of flue gas when exposing to low temperature water in the heat exchanger. According to performance test it can recover 45,200 to 51,000kJ/hr depending on the water circulation rates of 330 to $690{\ell}$/hr from the waste heat discharged. The exhaust gas temperature left from the heat exchanger dropped to $100^{circ}C$ from $270^{circ}C$ by the heat exchange between the water and the flue gas, while water gained the difference and temperature increased to $38^{circ}C$ from $21^{circ}C$ at the water flow rate of $690{\ell}$/hr. And, the condensed water amount varies from 16 to $43m{\ell}$ at the same water circulation rates. This condensing heat recovery system can reduce boiler fuel consumption amount in a day by 34% according to the feasibility study of the actual mimitomato greenhouse. No combustion load was observed in the hot air heater.

• 한국가스학회지
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• 제15권3호
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• pp.26-30
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• 2011

개방형 순간 가스온수기는 설치와 관리가 적절히 되지 않아 일산화탄소 중독과 질식과 같은 인명사고를 발생시킬 수 있다. 연소기에 공기가 충분히 공급되지 않거나 배기구가 막히면 배기가스 중의 일산화탄소(CO)의 농도가 증가하는 특성을 보인다. 본 연구는 가정집에서 사용 중인 개방형 가스온수기를 회수하여 연소기 주변 공기 중산소농도 및 배기가스 중 CO농도의 변화를 확인하였다. 환기구 면적에 따른 산소농도 측정 실험에서 환기구의 면적이 바닥면적의 3.5%에서 산소농도가 약 17.7%로 나타났고, 배기구를 폐쇄한 상태에서 CO농도를 측정한 결과 4,000ppm이상이 측정되었다. 따라서 정기적으로 배기구를 점검하는 것이 환기구 크기보다 일산화탄소 중독사고를 예방하기 위하여 중요하다.

• 동력기계공학회지
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• 제3권3호
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• pp.44-53
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• 1999

This study is concerned with the emission characteristics of kerosene fan heater, which is burned with kerosene and water droplets simultaneously in the burner, in order to prohibit the emissions of harmful exhaust gas and reduce smell caused by incomplete combustion, and the addition of water droplets to the conventional kerosene fan heater was performed by ultrasonic atomizer. For the investigation of this study, the measurement of exhaust gas components and exhaust gas temperature was carried out by using an automatic combustion gas analyser and $NO_x$ analyser, and the measurement of consumption weight of oil and water was obtained by using electric digital balance. Consequently, according as the water percent weight ratio of about $21{\sim}23%$ was supplied for this study, it was found that the combustion-generated $NO_x$ and CO emissions were reduced very largely, but the emissions of $O_2\;and\;CO_2$ and the temperature of exhaust gas were not changed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.599-602
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• 2008

This paper deals with the optimization of Gas-Gas-Heater elements for desulfurization equipment through flow analysis. The flow analysis model used in the paper is ${\kappa}-{\varepsilon}$ turbulent flow model. Temperature and flow velocity distributions for three types of panel elements are calculated. Through the analysis the following conclusions are obtained. Firstly, pressure differences of between inlet and outlet for three types of panel elements do not exceed in the standard pressure difference. Secondly, it is expected that NU-type panel element having wide area of heat transfer will be more effective in the aspect of the heat transfer.

• 센서학회지
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• 제19권3호
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• pp.197-201
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• 2010

This paper describes the fabrication and characteristics of a NO sensor using ZnO thin film integrated 3C-SiC micro heater based on polycrystalline 3C-SiC thin film of operation in harsh environments. The sensitivity, response time, and operating properties in high temperature and voltages of NO sensors based SiC MEMS are measured and analyzed. The sensitivity of device with pure ZnO thin film at the heater operating power of 13.5 mW ($300^{\circ}C$) is 0.875 in NO gas concentration of 0.046 ppm. In the case of Pt doping, the sensitivity of at power consumption of 5.9 mW ($250^{\circ}C$) was 1.92 at same gas flow rate. The ZnO with doped Pt was showed higher sensitivity, lower working temperature and faster adsorption characteristics to NO gas than pure ZnO thin film. The NO gas sensor integrated SiC micro heater is more strength than others in high voltage and temperature environments.

• 한국산학기술학회논문지
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• 제6권4호
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• pp.325-330
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• 2005

대기중의 일산화탄소 가스 농도를 측정하기 위한 마이크로 가스센서를 MEMS 공정을 이용하여 제작하였다. $SnO_2$ 가스 감응물질을 작동온도까지 가열하기 위하여 마이크로 히터를 설치하였다. 마이크로 히터에서 발생한 열이 효율적으로 감응물질에만 전달되고 실리콘 베이스로 누설되는 것을 최소화하기 위하여 마이크로 히터와 전극을 레버형으로 만들어 다리처럼 공중에 뜨게 하였으며, 이 위에 감응물질을 올려놓았다. 마이크로 가스센서의 열전달 현상을 상용 열유동 해석 전용 프로그램인 FLUENT를 이용하여 해석하였다. 해석 결과 실리콘웨이퍼 베이스의 온도가 거의 상온에 가까워 마이크로 히터에서 발생한 열이 가스 감응물질을 효과적으로 가열하여서 가스 감응물질의 열적 고립상태를 유지하고 있는 것을 알 수 있었다. 또한 감응물질을 작동온도까지 가열하기 위하여 마이크로 히터에 가하여야 하는 전류의 양을 예측할 수 있었다.

• 센서학회지
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• 제13권4호
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• pp.292-297
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• 2004

Carbon nanotubes (CNT) were synthesized by arc-discharge method. To fabricate CNT sensor, CNT powder was dispersed in ${\alpha}$-Terpinol($C_{10}H_{17}OH$) solution. The CNT tilms were fabricated by screen printing method on the interdigitated Pt/Pd alloy electrode. The microstructure of CNT film was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In order to investigate the gas sensing characteristics of the film, the CNT film was experimented to measure NO response and recovery time. The CNT sensor with a heater was compared to that without a heater. And this sensor shows better reproductibility and faster recovery time than another CNT sensors. We suggest the possibility to utilize a CNT as new sensing materials for environmental monitoring.

• 한국소음진동공학회논문집
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• 제16권9호
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• pp.964-970
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• 2006

Micro gas turbine(MGT) has received attention recently as small-scale distributed power sources. With characteristics such as their small size, lightweight, low maintenance cost and minimal vibrations during operation, they are expected to become widespread in a wide range of ' applications, including residential and small-scale industrial use. It is very easier to start-up and stop the MGT system which is the friendly environmental power system has just below the 9ppm NOx emmission and good quality of noise level. The exhaust heat emitted by the MGT is in the form of about $300^{\circ}C$ clean exhaust gas. The exhaust gas is suitable for absorption chiller/heater system. 1 has researched performance characteristics of the 60 kW class MGT-absorption chiller-heater system in the local condition. Variations of heat recovery from exhaust gas has measured according to micro gas turbine output of 15, 30, 45, 60kW. From those results, the performance of the MGT-absorption chiller/heater system has been evaluated.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2006년도 제26회 춘계학술대회논문집
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• pp.321-326
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• 2006

초음속 유도무기에 사용되고 있는 공기흡입 추진기관의 지상 연소시험에서 요구되는 700K-6바의 공기를 공급하기 위한 Vitiated형 공기 가열기에 대한 개념설계를 수행하였다. 본 가열기는 여분의 기체 산소와 공기를 혼합하는 예혼합기, 예혼합 기체와 연료를 혼합시키는 혼합기, 점화기를 포함하는 연소실과 수축팽창 노즐, 그리고 디퓨저로 구성하였다. 가열기에 사용된 연료는 천연가스이며, 유동해석을 통해 가열기의 각 구성요소의 성능을 파악하였으며, 점화 후 화염유지가 이루지는 것을 해석적으로 확인하였다.