• 대한기계학회논문집
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• 제9권1호
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• pp.64-70
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• 1985

본 연구에서는 관내분류에 관한 수치 해석을 Reynolds응력 모델 즉 5방정식 모델을 사용하여 흐름의 특성을 구명키로 하였다.

• 설비공학논문집
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• 제4권2호
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• pp.106-115
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• 1992

Numerical analysis of the laminar natural convection in an enclosure of the 20KVA oil-immeresed transformer is presented. The core in the transformer is modelled as a rectangular cylinder and calculation is carried out for $Ra=10^3-10^6$. The correlating equation between the inner cylinder mean Nusselt numbers and Rayleigh numbers can be obtained. The conduction and convection regimes for the variation of Rayleigh numbers are well represented in the temperature distributions along the side wall of the inner cylinder. For high Rayleigh numbers, it is found that the recirculating flow in the enclosure above the inner cylinder is divided into two recirculation regions.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.956-961
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• 2000

This paper describes the design of a small size Alkali Metal Thermal to Electric Converter (AMTEC) which employs a capillary structure for recirculating sodium working fluid. The cycle is based on the simple and small capillary type ${\beta}"$ -alumina and wick tube element. The proposed cell consists of the 37 conversion elements with capillary tube of $50{\mu}m$ in diameter and the sealed cylindrical vessel of 22mm in outer diameter. Results on the cycle analysis of sodium flow and heat transfer in the cell showed that the expected power output was 4.65W and the conversion efficiency was 19% for the source temperature of 900K.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.778-784
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• 2002

FFU are used increasingly by the microeleceronics industry to provide clean recirculating air for the fabrication of integrated circuits and laminar flow air. There may be several hundred ffu in a large cleanroom, covering 100% of the ceiling area. Hence, there is of often knowledge in the inside and outside of the country the flu give rise to noise & vibration trouble to microelectronics industry. Noise ＆ Vibration control for satisfication about noise ＆ vibration criteria in TFT-LCD factory cleanroom be in need of exact noise & vibration data of accurence from utility & equipment that can be exert a bad influence upon cleanroom. In this pater, hence we found out noise and vibration properities of ffu by using experimental method. And, we performed noise ＆ vibration analysis about noise it vibration level in cleanroom using semiempirical method for quantative approach about noise ＆ vibration level in cleanroom.

• Journal of Pharmaceutical Investigation
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• 제17권1호
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• pp.15-21
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• 1987

Effects of phenobarbital pretreatment on the pharmacokinetics of enterohepatic recirculating griseofulvin were investigated by comparing normal to bile duct cannulated rats and also the effects of enhanced endogeneous bile flow on the absorption of griseofulvin were studied by means of in situ recirculation method in phenobarbital-pretreated rats. Phenobarbital was administered orally for five days at the dose of 75 mg/kg/day. The influence of phenobarbital pretreatment on the absorption rate constant, area under the plasma concentration-time curve, maximum plasma concentration of orally administered griseofulvin was not found in bile duct cannulated rats. Decreased absorption clearance and apparent partition coefficient of griseofulvin in accordance with the amount of endogeneous bile juice seemed to be due to the decrease of thermodynamic activity of griseofulvin as bile forms the micelle with griseofulvin.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1995년도 춘계학술발표회 초록집
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• pp.60-68
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• 1995

This work wes performed to investigate the photocatalytic decolorization of waste water from textile industries. Methyl orange was used as a target dye with suspended Hombikat TiO$_2$ photocatalyst with a recirculating annular photoreactor. 1 wt % Pt-doped Hombikat thin film tubular reactor with parabolic reflector also wes usedin this experiment. The pH effect and flow rate effect on photobleaching of 0.012 g/l methyl orange solution, AtpH=3 Colour of methyl orange was completely bleached in 30 min with a 20 W UV lamp.

• 한국화재소방학회논문지
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• 제19권2호
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• pp.37-44
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• 2005

가스계소화설비인 $CO_2$소화장치의 구성 중 $CO_2$노즐수에 따른 유동특성 및 $CO_2$소화제 농도분포를 분석하기 위하여 $CO_2$ 노즐수를 변화시키면서 전산모사실험을 3차원 비정상상태로 수행하였다. 실제 선박의 기관실을 방호공간으로 선정하여 유동장과 $CO_2$소화제 농도장을 계산하였다. $CO_2$소화제 노즐수를 2개에서 4개로 증가시킬 경우는 낮은 농도분포를 나타냈고, $CO_2$소화제 노즐수를 6개 이상으로 증가시킬 경우는 전 영역에 영향을 미치는 재순환 유동이 형성되었다. $CO_2$소화제 노즐수를 4개 이상 증가시킬 경우는 0.36이하의 등농도선대가 확장 또는 수축되었다. 따라서 $CO_2$ 소화장치 설계 시 적정한 소화제노즐수와 노즐배열을 고려해야 할 것으로 생각된다.

• Asian-Australasian Journal of Animal Sciences
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• 제33권7호
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• pp.1209-1216
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• 2020

Objective: The present study aimed to evaluate the performance of odor abatement by using two different ventilation-biofilter systems with recycled stablized swine wastewater. Methods: The performance of odor removal efficiency was evaluated using two different ventilation-biofilter-recycled wastewater arrangements. A recirculating air-flow ventilation system connected to a vertical biofilter (M1) and a plug-flow ventilation system connected to a horizontal biofilter (M2) were installed. Water dripping over the surface of the biofilter was recycled at a flow rate of 0.83 L/h in summer and 0.58 L/h in winter to reduce odorous compounds and particulate matter (PM). The experiments were performed for 64 days with M1 and M2 to investigate how these two ventilation-biofilter systems influenced the reduction of odor compounds in the model houses. Odorous compounds, NH₃ and volatile organic compounds (VOCs) were analyzed, and microclimatic variables such as temperature, humidity, and PM were monitored. Results: Ammonia concentration inside M1 was about 41% higher on average than that in M2. PM and total suspended particles (TSPs) inside M1 were about 62.2% and 69.9%, respectively, higher than those in M2. TSPs in the model house were positively correlated with the concentration of NH₃ and VOCs. Conclusion: M2 emitted lower concentration of odorous compounds than M1. Moreover, M2 could maintain the optimum temperature condition for a swine house during the cooler season. The plug-flow ventilation-horizontal biofilter system could be used for pig houses to minimize air pollution produced by swine farming activities and maintain optimum microclimate conditions for pigs.

• 한국산학기술학회논문지
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• 제15권6호
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• pp.3370-3375
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• 2014

MILD(Moderate and Intense Low Oxygen Dilution) 연소는 열효율 향상과 유해배출가스 저감의 상반된 관계를 해결하기 위한 하나의 각광받는 기술이다. 연소가스의 재순환을 이용하여 고온 연소시에 질소산화물을 낮게 유지함과 동시에 연소로 내부온도를 균일화함으로써 열효율을 향상시킬 수 있는 기술이다. 본 연구는 실험실 규모의 노에서 원추형 MILD 연소기의 연소특성을 나타내고 있다. 연구의 조건은 공기의 유량은 일정하게 하면서 가스 연료 유량을 변화시켜 당량비를 변화시켰다. 이 결과 노 내에서 MILD 연소영역이 잘 구현되었고, 당량비 0.69~0.83의 범위에 걸쳐서 노(爐)내에서의 온도와 배출가스의 농도가 각각 예측되었다. 이 당량비 구간에서 최고화염온도 영역과 주 반응영역에서의 온도차가 약 $300^{\circ}C$의 안정적인 화염 영역의 존재를 확인하였다.

• 대한기계학회논문집B
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• 제41권9호
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• pp.623-629
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• 2017

다공배플을 가진 마이크로연소기에 레이놀즈응력 난류모형을 이용하여 난류유동 및 혼합특성에 대한 수치해석 연구를 수행하였다. 다공배플은 연소실 내부에 다수의 3차원 와유동을 발생시키는 기하학적 특징을 가지고 있다. 그러한 형상특징 중에서 배플두께를 변화시킬 경우 와유동구조의 다양한 변화가 얻어졌다. 여러 와유동중에서 연료유동으로부터 생성된 와유동은 혼합도 증가에 결정적 역할을 하였다. 연소실 내부의 3차원 와유동구조는 배플두께 변화에 따른 유동의 발달상태에 의존하였다. 특히, 배플두께가 연료유입구 직경보다 작을수록 배플구멍 제트유동의 속도분포는 포물선형태에서 안장모양의 형태로 변하였다. 연소실내부의 재순환영역크기 및 혼합도는 이러한 제트유동구조에 밀접한 상관관계를 가졌다.