• 설비공학논문집
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• 제17권7호
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• pp.669-680
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• 2005

The purpose of this study is to develop the air-conditioning unit combined with the lighting unit for workspace and to supply its performance data at architectural design stage. The air-conditioning unit is one of the components of a workspace integrated unit, which can be defined as the planning unit satisfying the environmental comfort criteria of workspace. Air-conditioning diffusers are classified according to throws and features by literature review and case study. Then diffusers are combined with the lighting unit. Through the CFD simulation, the thermal performance of each unit was evaluated and finally various air-conditioning units combined with the lighting units were developed.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.583-590
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• 2008

최근 작업자 숙소 및 이송용 외에 작업용으로 사용 가능한 Barge선의 일종인 Accommodation Work Barge 선의 건조량이 증가 추세인 바 현재 중국에서 건조 중인 해당 선박의 HVAC & Refrigeration system에 대하여 정리하였다. 본 시스템은 R404A Direct expansion 냉각방식 (직접팽창방식)이 적용되었으며 HVAC system 중 Air conditioning 부분에 대해서는 선박의 각 Deck 기준으로 Zoning 하여 개별적인 Air handling unit와 Condensing unit를 구성하였으며 (각 unit의 용량은 필요용량의 100%), 냉동 창고의 Refrigeration system은 해당 격실 (육고, 어고, 야채고)에 각각 Unit cooler를 설치하고, Condensing unit를 기계실에 설치하였다. 장비는 전체 용량 100%에 대하여 항시 운전하는 100% 용량의 장비와 비상시에 운전하는 100% 용량의 예비 장비로 구성된다. 냉동 창고에 인접한 Dry provision store는 냉동 창고와는 별개로 중앙 공조기로부터의 냉각 공기를 이용하여 Spot cooling하였다. 본 System의 구성에 대한 장점 및 단점은 아래와 같다. 1. Air conditioning system이 각 Zone에 대하여 구성되므로 각 Zone에 대하여 제어가 가능하다. 2. Air con. 실에 Air handling unit와 Condensing unit가 설치되므로 냉매 배관의 길이가 짧다. 3. Air con. 실에 Air handling unit와 Condensing unit가 설치되므로 실내의 Maintenance space 상에 여유가 없다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.591-596
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• 2008

The present study has been conducted to study the performance of dedicated outdoor air handling unit in central and personal air-conditioning. With conventional central and personal air-conditioning systems which are designed according to the maximum load, humidity increase above comfort level can not be avoided as the cooling load decreases. The adoption of dedicated outdoor air handling unit, however, can solve this problem. Moreover, the dedicated outdoor air handling unit has the characteristics of anti-bacteria due to dry coil, energy saving and good indoor air quality. During cooling seasons, dedicated outdoor air handling unit can save energy up to 30% than the conventional cooling+reheating system for controlling both temperature and humidity.

• 설비공학논문집
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• 제16권9호
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• pp.872-880
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• 2004

The fault detection and diagnosis technology may be applied in order to decrease the energy consumption and the maintenance cost of the air-conditioning system. In this study, an air handling unit fault test apparatus was built and fault diagnosis algorithms were applied to diagnose various faults of an air handling unit. Test results showed the good diagnosis for applied faults. Therefore, these algorithms may be effectively used to develope the real time fault detection and diagnosis system for the air handling unit.

• 한국산학기술학회논문지
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• 제13권11호
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• pp.4944-4949
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• 2012

이 논문의 목적은 작업장에서 사용하기 위한 에어건의 개발에 관련된 것이다. 에어건은 공작기계를 사용하는 산업현장에서 공작물 칩과 절삭유의 제거를 위한 도구이다. 그리고 그것은 일반적으로 압축공기를 분사하는 용도로 사용된다. 작업자는 에어의 흡입과 분사를 위해 각각의 에어건을 준비하여야 한다. 따라서 우리는 새로운 에어건을 개발하였다. 이 논문에서 우리는 에어건의 설계와 분석을 위한 연구를 한다. 에어건은 몸체, 파이프, 개폐 유닛, 전환 유닛, 에어 튜브 그리고 조립을 위한 요소들로 구성된다. 개발된 에어건은 그 효율을 확인하기 위해 실험된다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.577-582
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• 2008

The present study has been conducted to study the performance of Dedicated outdoor air handling unit. Dedicated outdoor air handling unit consists of pre-cooler, dehumidification and after cooler. By combining dedicated outdoor air-conditioning and heat pump, a new four-season dedicated outdoor air handling unit has been developed. Amount of energy saved and condition when this new system is superior to conventional vapor-compression cooling system has been presented.

• 한국전산유체공학회지
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• 제15권4호
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• pp.92-98
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• 2010

In a modern high speed drawing process of optical fibers, it is necessary to use helium as a cooling gas in a glass fiber cooling unit in order to sufficiently cool down the fast moving glass fiber freshly drawn from the heated silica preform in the furnace. Since the air is entrained unavoidably when the glass fiber passes through the cooling unit, the helium is needed to be injected constantly into the cooling unit. The present numerical study investigates and analyzes the air entrainment using an axisymmetric geometry of glass fiber cooling unit. The effects of helium injection rate and direction on the air entrainment rate are discussed in terms of helium purity of cooling gas inside the cooling unit. For a given rate of helium injection, it is found that there exists a certain drawing speed that results in sudden increase in the air entrainment rate, which leads to the decreasing helium purity and therefore the cooling performance of the glass fiber cooling unit. Also, the helium injection in aiding direction is found to be more advantageous than the injection in opposing direction.

• Advances in environmental research
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• 제1권4호
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• pp.277-288
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• 2012

This study investigated exposure to air pollutants in rooms in low-income houses at Shomolu (R1), Mafoluku (R2) and Mushin (R3) in Lagos state. The concentrations of most measured exceeded limits of Illinois Department of Public Health (IDPH) for indoor air quality. Air quality index (AQI) in rooms studied was unhealthy for sensitive people in terms of CO, unhealthy in terms of $SO_2$ and very unhealthy in terms of $NO_2$ while moderate air quality was obtained in terms of $PM_{10}$ in most rooms. High concentrations of carbontetrachloride, formaldehyde and xylene measured could have been responsible for some of the health complaints of the occupants. Factor analysis shows that cooking with kerosene, use of gasoline generator and insecticide were the major contributors to indoor air pollution in these rooms. Therefore, there is need to urgently tackle poverty as all affected by these pollutants were poor who live in substandard houses without kitchens.

• 설비공학논문집
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• 제15권3호
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• pp.203-209
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• 2003

Control algorithms of an air handling unit by using the mixing box plenum pressures were developed and verified by experiments. Control algorithms developed for this study were the setpoint algorithms for the outdoor damper position, the outdoor/fixed plenum pressure, and the return/exhaust plenum pressure. The outdoor/fixed plenum pressure setpoint was used to control the bypass damper position, and the return/exhaust plenum pressure setpoint was used to control the return fan speed. Experimental results showed the good control of the required outdoor air demand. Therefore, setpoint algorithms developed for this study may effectively be applied for the control of the VAV air handling unit.

• 대한설비공학회지:설비저널
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• 제17권4호
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• pp.442-447
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• 1988

To keep comfortable indoor condition, the existing air conditioning system is controlled by the ON/OFF temperature controller. The PID control unit is developed to control temperature and humidity simultaneously, and the Air-conditioning control system is transferred from the ON/OFF temperature controller to the PID control unit for experiment. As a result of this experiment, the PID control unit reduced energy consumption compared with the ON/OFF control unit.