• 대한기계학회논문집
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• 제13권4호
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• pp.708-716
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• 1989

본 연구의 목적은 고속도 카메라로 촬영된 순간사진들로부터 액주면의 파장, 진폭, 파의 진행속도 및 교란의 성장속도 등을 측정하여 액주의 분열에 미치는 기류 및 액량의 효과를 구하였고, 또 이것을 선행 연구자들의 이론 및 실험과 비교분석하여 액주의 분열 기구를 밝히는 데 있다.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제14권4호
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• pp.39-46
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• 2008

Construction and operation of Germ Free Pigs' facilities are very expensive because pigs' rooms and other major rooms of the facility require germfree environments. Especially, running the HVAC system of aseptic facilities requires a lot of expenses. However, proper location and efficient shape of outlets/inlets for the ventilation of the room can reduce the excessive running cost. In order to do that, this study proposes alternative location and shape of ventilation outlets/inlets to the existing design pattern in germfree pigs' room. The design condition of this study is the maintenance of adequate temperature(24$^{\circ}C$, $NH_3$concentration level(below 1.5 ppm), and air stream speed(below .25m/sec) in the pigs' room for the summer and the winter together. As the Software Program, FLUENT(Ver. 6.2) has been used for the analysis of proposed ventilation patterns. In conclusion, wall inlets and ceiling inlet/outlet are advisable in summer, wall inlets and ceiling outlets is advisable in winter. As far as the shape is concerned, diffuser type for the ceiling outlet is desirable.

• 한국농공학회논문집
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• 제54권5호
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• pp.79-89
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• 2012

The objectives of this paper were to evaluate the wind flow behind the livestock ventilation fan for small-scale wind power generation and to make flow profiles of imaginary ventilation fan for future simulation works. The field experiments using typical 50-inch fan indicated that the wind flow behind the ventilation fan had a good possibility of power generation with its high and steady wind speeds up to a distance of 2 m. The expected electricity yield was almost 101~369 W with a small (0.8 m radius) wind turbine. The decline of ventilation fan performance caused by the obstacle was also not significant with about 4 % from a distance of 2 m. The flow profiles for the computational fluid dynamics (CFD) simulation was created by combining the direction vectors analyzed from tuft visualization test and the flow predicted by the rotating fan modeling. The flow profiles are expected to provide an efficient saving of computational time and cost to design a better wind turbine system in future works.

• Animal Systematics, Evolution and Diversity
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• 제16권2호
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• pp.227-237
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• 2000

남한의 수 개 지역에서 채집한 3과 8종의 톡토기 가운데 6종 (Oudemansia esakii (Kinoshita, 1932), Axelsonia littoralis (Moniez. 1890), Sinella (S. str.) straminea (Folsom. 1899), Sinella (S. str.) coeca (Schott, 1899), Entomobrya marginata (Tullberg, 1871), Willowsia bimaculata (Borner, 1909))이 한국 미기록종으로 판명되어 보고한다. 이 중 Oudemansia esakii, Axelsonia littoralis와 Entomobrya marginata 3종은 호염성이고, Sinella straminea와 Sinella coeca는 개미집에서 채집되었다. Sinella속의 2종은 한반도에서 개미집으로부터 채집된 톡토기의 첫 보고이다. 본 조사 결과 한국산 톡토기는 모두 10과 204종에 이른다.

• 한국터널지하공간학회 논문집
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• 제14권2호
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• pp.107-116
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• 2012

네트워크형 도로터널 내 분기부 구조물과 제트팬에 의한 분기 환기효율 분석하고자 실제 도로터널을 1/45로 축소하여 실험을 수행하였다. 차량이 주행할 때 발생하는 교통관성력을 적용하기 위해 블로워 팬를 사용하여 축소모형 터널내 기류를 형성하였고, 터널의 국부적인 위치에서 속도를 측정하여 분기 효율을 연구하였다. 구조물의 특징으로 발생되는 환기 저감을 개선하기 위해 제트팬을 설치하여 터널 내 환기 효율을 최적화하였다.

• 설비공학논문집
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• 제21권7호
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• pp.409-416
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• 2009

On 21st century, global warming is the most serious environmental problem threatening the existence of lives on the earth. One of the serious reasons of this nature phenomena was due to the greenhouse effect by carbon dioxide mainly produced with the combustion process of hydro-carbon fuel. and it is mostly produced. In the high oil prices age, intensification of energy efficiency promotion in the building sector is required. Windows are dominating large percentage whole building loads, and are regarding as the primary target of energy efficiency. The purpose of this research is on the obtaining of the renewable energy source in the skyscrape buildings in the metropolitan area. The air movement is happens due to the atmospheric pressure differences in the air. Due to this simple physical theory, it is easily expected to obtain the useful renewable nature energy through the high -raised vertical air stack installed in a tall building. However, there is one problem that should be resolved which is called air-hole effect in the sky -scrape buildings.

• 설비공학논문집
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• 제16권3호
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• pp.303-309
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• 2004

In order to improve thermal comfort in the Rotunda, which is high and wide visiting space of the new national museum of Korea, eight ventilating fans were installed near the ceiling of Rotunda. It has been analyzed thermal comfort of Rotunda with/without ventilating fans by numerical simulation. To evaluate thermal comfort of the Rotunda, well-known indices, PMV and PPD were introduced. The results of present investigation show that temperature distribution of the case with fans is closer to target temperature than the case with-out fans at the breathing zone. In the case without fans, thermal stratification with 16$^{\circ}C$ of temperature difference occurs along the height of the Rotunda which makes the thermal environment worse and the PPD values reach up to 50% in the 6th floor connection passage. In the case with fans, however, the vertical temperature difference were reduced to 9$^{\circ}C$ and the PPD values were lower below 20%. Consequently, the ventilating fans adopted on this study are effectively used for improving the thermal comfort in large space structure with thermal stratification.

• 설비공학논문집
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• 제12권1호
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• pp.75-82
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• 2000

This paper presents the predicted results by CFD technique of air flow and contaminant distribution in a full-scale kitchen opened to a living room, ventilated by a exhaust hood. To analyze the characteristics of the indoor environment, the concept of contaminant index was defined. In this study, the locations of the gas range and the window were chosen as the parameters to investigate the indoor environment. The values of the contaminant index for several layout of the gas range and the window were calculated and compared. When the gas range is installed along the wall with specified window location, its position in relation to the wall has unnoticed effect on contaminant infer. Once the location of the gas range is fixed, the indoor air quality may deteriorate by the proximity of the window to the gas range. This is due to the shorter distance that external fresh air must travel within the kitchen before it reaches the exhaust fan.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.311-318
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• 2006

CFD simulation is a tool very useful to predict the generation and absorption of the contaminant from the construction materials for the single room condition. However, there is a limit in multi-room simulation for analyzing air movement and contaminant concentration at the condition that the door of each room was closed. A lot of network simulation tool were developed which can used to analyze the mass transfer and contaminant concentration as results in the multi-room condition. However, existing network simulation method was not able to analyze the change of the heating and cooling load with the ventilation as though the change of the indoor air-pollution density was predictable. In this study, new approach to predict heating/cooling load and indoor contaminant concentration will be reviewed. New indoor contaminant concentration module reviewed in this study wad coupled with existing ESP-r network simulation method. The validity of new approach will be analysed for comparison the results of simulation and field measurement results.

• 설비공학논문집
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• 제15권8호
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• pp.683-689
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• 2003

The thermal comfort of an indoor swimming pool is different from that of general indoor space because of the characteristics of large space and the wear conditions of swimmers. Dew condensation by humid air not only makes mold on the floor, wall and roof but also decreases the durability of buildings by penetrating into their structures. In this study, the characteristics of the flow field, the temperature field and the humidity distribution in an indoor swimming pool have been examined by the numerical method to estimate the level of thermal comfort and the generation rate of dew condensation. The results showed that the dew condensation regions were spread widely at the eastern parts of the swimming pool due to the insufficient air flow rate with low velocity and temperature. To prevent the generation of dew condensation in a region, a sufficient warm air flow rate should be supplied to make an air mixing. The values of PMV at horizontal plane of 1.5 m height have the range of -1.0∼1.2, which means the suitable level for swimmers.