• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1998년도 추계학술발표회 논문 초록집
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• pp.17-19
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• 1998

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.980-983
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• 2004

• 설비공학논문집
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• 제1권1호
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• pp.32-45
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• 1989

The airflow characteristics of clean tunnel type clean room were experimentally investigated with the change of operating speed and exit type. Distributions of air velocity and pressure were measured in clean room which is located lower than HEPA filters, and the pressure distribution was also measured in upper plenum which is located above the HEPA filters, to identify the performance of clean room. Through the analysis it was turned out that air velocity characteristics in clean room were significantly affected by the upper plenum flow conditions such as pressure distribuion. This results will be useful in the actual clean room design to enhance the performance.

• 설비공학논문집
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• 제13권6호
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• pp.524-531
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• 2001

The temperature and humidity distribution in a dry room are studied numerically by using standard$\kappa-\varepsilon$ turbulence model. In order to evaluate effective heat and moisture ventilation characteristics inside the room, the heat removal capacity and moisture exhaust efficiency are introduced. An effective ventilation control is analyzed by evaluating quantitatively temperature and humidity distributions. It was found that the mean absolute humidity inside the room was almost constant with approximately 0.1905g/kg air regardless of the models and the heat generation rates. This was believed that the moisture generation by workers was relatively small. 40% improvement of the critical decay time was achieved, through the modifications of design variables.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제24권2호
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• pp.37-44
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• 2018

Purpose: This study investigates the influences of coughing direction and healthcare worker's location on the transport characteristics of coughed particles in airborne infection isolation room (AIIR), which is commonly called negative pressure isolation room, with a downward ventilation system. Methods: Computational Fluid Dynamics (CFD) was used to simulate the airflow and for tracing the behavior of particles. Results: The results show that the airflow pattern and coughing direction have a significant influence on the characteristics of particle dispersion and deposition. When healthcare workers are in the isolation room with the patient who is lying on the bed, it is recommended to be located far from the anteroom to reduce the exposures from infectious particles. And when the patient is lying, it is more effective in removing particles than when the patient is in Fowler's position. Although it is an isolation room that produces unidirectional flow, coughing particles can spread to the whole room and a large number of particles can be deposited onto patient, bed, side rails, healthcare worker, ceiling, floor, and sidewall. Implications: Following the patients' discharge or transfer, terminal cleaning of the vacated room, furniture, and all clinical equipment is essential. Also, it is necessary to establish detailed standard operating procedure (SOP) in order to reduce the risk of cross-contamination.

• 한국화재소방학회논문지
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• 제31권4호
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• pp.52-58
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• 2017

본 연구에서는 급기가압에 따른 건축물 내부의 공기유동에 대한 수치해석을 수행하고 거실, 부속실 및 계단실 간의 차압분포 및 유동 특성을 분석하였다. 유동 해석은 유효누설면적을 측정하기 위해 제작된 누기율 시험설비에 대하여 수행하였으며, 급기가압에 따른 각 실의 압력 및 유속분포 등을 분석하였다. 본 해석에서 공기의 누설은 유효누설면적을 갖는 얇은 틈새를 방화문과 창문에 위치시키는 방법으로 모사하였다. 이러한 방법을 이용한 해석은 계단실과 부속실 간의 차압에 대한 기존 실험의 결과를 적절히 예측하였다. 해석 결과를 통해 국부적인 누설이 급기가압 제연 설비의 전체적인 유동 패턴 및 압력 분포에 큰 영향을 미치지 않음을 확인하였다. 거실-부속실 문 단면에서의 평균속도가 방연풍속에 대한 국가화재안전기준을 만족하였으나 문의 상부와 같은 국부적인 위치에서 부속실로의 유출이 발생할 수 있음을 확인하였다.

• 한국안전학회지
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• 제36권1호
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• pp.86-94
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• 2021

Lecture rooms are crowded with many attendees. Moreover, they rely significantly on the natural ventilation through windows for removing and controlling indoor contaminants such as CO₂. With the aim of broadening the understanding of the characteristics of natural ventilation phenomena in lecture rooms, the average individual CO₂ release rates of attendees were measured during the course of a lecture and compared with previously reported CO₂ release rates. In addition, the effects of natural ventilation through windows on the time-variant CO₂ concentrations in the center of the lecture room were measured and analyzed. Moreover, details about the overall and regional CO₂ concentrations, as well as the air flows in the lecture room, were simulated and analyzed with computational fluid dynamics software, Fluent 2020 R2. It was found that the average individual CO₂ release rates were slightly slower than previously reported rates. The local CO₂ concentrations in the lecture room for regions with a high density of attendees increased over a short period of time, although the natural ventilation was already started by opening the windows. The overall CO₂ concentration in the lecture room rapidly decreased in the early stage of ventilation, but declined very slowly after a longer period of ventilation time. Therefore, in order to enhance the efficiency of a lecture room's natural ventilation, it is recommended to homogeneously distribute the attendees in the lecture room, and to frequently open the windows for short periods of time.

• Journal of Advanced Marine Engineering and Technology
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• 제30권1호
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• pp.50-57
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• 2006

This study describes to analyze the cooling load characteristics for a room air conditioner as a function of supply ventilation air when an air conditioner is running An experimental apparatus consists of a test room, a room air conditioner, a humidifier, an electrical heater a supply fan and a controller The reaching time to the inside setting temperature of the room air conditioner with is evaluated theoretically and experimentally in a conditioned space cooling loads such as supply ventilation air, lighting, occupancy and infiltration. In the conditions of cooling loads for the supply ventilation air of 9.5 L/s(0.98 ACH). lights. one Person, and infiltration, the reaching time to the inside setting temperature ($27\;^{\circ}C$ dry-bulb) increases up to $35\%$ more than for no supply ventilation air condition. Theoretical modelling of the reaching time shows good agreement with experimental results.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.150-155
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• 2006

Speech intelligibility is investigated on a conference room-window glass coupled system. Using MLS(Maximum Length Sequency) signal as a sound source, acceleration and velocity responses of the window glass are measured by accelerometer and laser doppler vibrometer. MTF(Modulation Transfer Function) is used to identify the speech transmission characteristics of the room and window system. STI(Speech Transmission Index) is calculated by using MTF and speech intelligibility of the room and the window glass is estimated. Speech intelligibilities by the acceleration signal and the velocity signal are compared and the possibility of the wiretapping is investigated. Finally, intelligibility of the conversation sound is examined by the subjective test.

• 동력기계공학회지
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• 제2권3호
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• pp.27-33
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• 1998

The room temperature and air conditioning load in the underground space have been investigated numerically by the unsteady heat conduction equation. The model room has 3 m in height and 10 m in width, and it's position in the underground depth are 0.5 m to 5 m. When the room was located around surface, the room temperatures were strongly influenced by the atmosphere. But the underground depth is more than 2 m, the yearly temperature amplitude was small and the temperature phase was delayed. Up to 5 m of the depth, the cooling and heating load was decreased rapidly, but over 10 m of the depth, the air conditioning load was constant.