• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.520-525
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• 2000

This research is to analyze the ventilation performance of mechanical ventilation systems for indoor air quality control and management. A ventilation performance with supply sites is evaluated in a test model chamber and office room. A $CO_2$ gas as a tracer gas is used to measure the ventilation performance. The ventilation performance is found to increase with increased the ventilation rate. The ventilation performance is analysed with 55% at the supply air of 570 lpm and with 20% at the supply air of 100 lpm in a test chamber. The ventilation performance is better than 15% comparing with natural decay at the supply of 570 lpm in office room.

• 설비공학논문집
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• 제13권6호
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• pp.448-454
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• 2001

In the present study, the transient axi-symmetric numerical simulation of traffic ventilation induced by a train running through a 15.6km-long tunnel is performed by using over 100,000 computational cells. With train running, three cases of ventilation schemes are simulated, which are the case of ventilation fans turned on, the case of no fan but ventilation shafts open, and the case of no fan and no shaft. Results of the ventilation flow rate are pressure transients are compared for the cases considered.

• 한국산학기술학회논문지
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• 제9권6호
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• pp.1523-1528
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• 2008

본 논문에서는 지하주차장 연결통로 및 엘리베이터 홀의 기계식 환기장치의 설치 및 적용을 위한 기초자료를 얻기 위하여 공동주택 지하주차장에 환기장치를 설치하여 실험을 수행하였다. 엘리베이터 홀의 경우 침기 및 누기(자연환기)로 인하여 실제 환기회수는 계산환기회수의 5배 정도 크게 나타났다. 지하 주차장 연결통로 및 엘리베이터홀의 환기장치는 동시 급 배기로 설치하는 것이 좋으며, 설치가 어려울 때에는 차선책으로 급기만이라도 설치하는 것이 공기질 측면에서 좋을 것이라 판단된다. 겨울철 환기장치 가동에 따른 콜드 드래프트의 영향을 고려하여 환기장치의 급기부에 예열기를 설치하는데, 환기시스템의 가동유무 및 가동방법을 다르게 하여도 지하주차장 연결통로 및 엘리베이터 홀의 온도가 $7{\sim}8^{\circ}C$로 일정하게 유지되어 나타나므로 한국의 남부지역에서는 단순 급 배기 환기장치에 예열기를 설치하지 않아도 될 것으로 판단된다.

• 한국농공학회논문집
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• 제65권1호
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• pp.61-72
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• 2023

The increase in the rearing intensity of pigs has caused deterioration in the pig house's internal environment such as temperature, humidity, ammonia gas, and so on. Traditionally, the widely used method to control the internal environment was through the manipulation of the ventilation system. However, the conventional ventilation system had a limitation to control the internal environment, prevent livestock disease, save energy, and reduce odor emission. To overcome this problem, the air-recirculated ventilation system was suggested. This system has a semi-closed loop ventilation type. For designing this system, it was essential to evaluate the ventilation rates considering the pressure loss of ducts. Therefore, in this study, pressure loss calculation and experiment were conducted for the quantitative ventilation design of a semi-closed loop system. The results of the experiment showed that the inlet through which external air flows should always be opened. In addition, it was also found that for the optimum design of the semi-closed loop ventilation system, it was appropriate to install a damper or a backflow prevention device rather than a ventilation fan.

• 한국환경보건학회지
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• 제33권4호
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• pp.255-263
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• 2007

Indoor air quality is the dominant contributor to total personal exposure because most people spend a majority of their time indoors. The purposes of this study were to evaluate the alternative method for improvement of indoor air quality in house after coating titanium dioxide ($TiO_2$) photocatalyst for interior part of the house using nitrogen dioxide ($NO_2$) multiple measurements. To evaluate the alternative method in indoor environment, daily indoor and outdoor $NO_2$ concentrations of an apartment and a detached house were daily measured for consecutive 21 days in winter and summer, respectively, Another daily 21 measurements were carried out after $TiO_2$ coating on wall paper of interior part in houses. All $NO_2$ concentrations were measured by passive filter badges. Indoor air quality models using mass balance are useful tool to quantify the relationship between indoor air pollution levels, ambient concentrations, and explanatory variables. Using a mass balance model and linear regression analysis, penetration factor (ventilation rate divided by sum of ventilation rate and decay rate) and source strength factor (emission rate divided by sum of ventilation rate and decay rate) were calculated. Subsequently, the decay constants were estimated. In this study. magnitude of improvement of indoor air quality could be evaluated by decay constant.

• 설비공학논문집
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• 제23권12호
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• pp.828-835
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• 2011

The purpose of this study is to analyze and evaluate the 3 types of indoor ventilation methods such as natural, mechanical, and hybrid ventilation in high-rise building which is affected by stack effect and outdoor air pressure. For the evaluation of the ventilation capacity, CFD simulation was performed in a typical high-rise residential building. The results of the simulations are as follows: 1) Natural ventilation method is not enough to the regulation. 2) In case of mechanical ventilation, congested area is occurred but meets the regulation. 3) In case of hybrid ventilation with stack effect, all the areas of indoor meet the regulation and congested area is reduced. 4) In case of high-rise building, the differences of ventilation rate among houses in the building are not large because the mechanical ventilation is main factor.

• 한국가스학회지
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• 제16권2호
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• pp.31-37
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• 2012

본 연구는 실내 쾌적성 제어를 위하여 룸 에어컨의 환기성능을 분석한다. 실험장치는 환경공조챔버, 룸 에어컨, 추적가스 측정시스템, 급기팬과 제어기로 구성된다. 환기성능은 ASTM Standard E741-83 기준에 근거하여 환경공조챔버 내 CO2 추적가스기법을 사용한 체강법에 의해 재실자와 급기 환기량에 따라 평가된다. 급기 환기량 증가에 따라 환기성능이 증가함을 파악하였으며 재실자가 없는 경우 CO2 가스는 빠르게 감소하며 이때의 환기성능은 55%까지 증가한다. 그리고 1명의 재실자가 있는 경우 1시간 경과후 급기량 570 lpm에서 환기성능은 자연감쇠와 비교하여 25%까지 증가한다. 실험 데이터를 사용하여 환경공조챔버 내 룸 에어컨의 환기성능 모델링을 도출하였다.

• KIEAE Journal
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• 제12권1호
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• pp.29-34
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• 2012

As a series of studies about natural ventilation driven by wind in basement parking lots of apartment, the influence of opening size and surrounding buildings on ventilation rate was analyzed. Natural ventilation in underground parking lots almost rely on wind than temperature difference. To investigate natural ventilation driven by wind, wind tunnel tests by using scale model and tracer gas method were conducted. $CO_2$-gas concentration was measured, natural ventilation rates were calculated. The experimental results showed that the natural ventilation rate is more reliable to wind direction and surrounding building than opening size and distance between buildings. It was verified that surrounding buildings play a principal role in increasing air flow rate by accelerating wind speed, and growing turbulence intensity. And it showed that ventilation performance is able to be increased by oblique wind to entrance ramp than head on wind in underground parking lots with surrounding buildings.

• 설비공학논문집
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• 제16권5호
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• pp.482-489
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• 2004

The purpose of this study is to reevaluate the performance of Hanji as a architectural material. Recent studies report that one of the causes of the Sick-HouseㆍSick-Building Syndrome is due to the contaminants from interior materials and the lack of ventilation. In this study, the properties of Hanji are investigated. The major focuses of this research are (1) how efficient the Hanji is for ventilation of the house and (2) whether the usage of Hanji brings required ventilation volume to the house. According to the test results, differential pressure in the air and the amount of ventilation showed linear relationship. Test results differ from various kinds of Hanji. Since houses usually have double window system, Hanji can be used to the windows system, especially for inner part of double window system. It is suggested that the combination of Hanji windows for the inner part and glass windows for outer part is very effective, and offers a solution to improvement of indoor air quality and the lack of ventilation with passive ventilation that has less energy consumption.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.99-104
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• 2007

Tracer gas technique is widely used to measure the ventilation rates and/or ventilation effectiveness of building spaces. However, the conventional method using a single tracer gas can measure only outdoor air change rates in a single zone. This paper deals with the multi-gas tracer technique to measure air exchange rates between rooms. Interzonal air movements are important to characterize overall ventilation performance of complicated multi-zone buildings. Experiments are conducted in a simple two-room model with known airflow rates using tracer gases of SF6 and R134a. The concentration decays of two tracer gases are measured after simultaneous injections in each room. The governing equations are derived from the continuity and the mass balance of each room. The data reduction procedure are developed to obtain the inter-room airflow rates using the governing matrix inversion, and various data manipulation methods are tested, such as data shift, interpolation, smoothing, and etc, to improve the estimate and interpretation of the results.