공동주택 자연환기설비의 성능예측에 관한 연구

최용석(Choi Yong-Seok),김용식(Kim Yong-Sik) 대한건축학회 2007 대한건축학회논문집 Vol.23 No.11

This study evaluates the capability of natural ventilation facilities in an apartment house by using CFD analysis. Recently, the Ministry of Construction and Transportation decided that the the number of ventilation, 0.7th/h in apartment house with more than 100 household is mandatory and it is also required for the apartment house which has the natural ventilation facilities. CFD analysis is applied to the apartment house with 304 household in Seoul E-area and the natural ventilation performance in 40 py-unit is reported in this paper. Result are as following. 1) When the natural ventilating openings are installed in the house which have 2 side ventilating openings at south and north, the natural ones play roles of intake and exhaustion. Therefore, it is necessary to equip double natural ventilating openings for the current standard regulation. 2) Even though some of the units have natural ventilating openings of 3 sides (north/east/south in this research), which has a long enough natural ventilation path, the condition of 0.7th/h is not fully achieved because ventilation inflow and outflow parts are not separated. Hence, such a coexistence type not like cross ventilation type needs more investigation to calculate the exact amount of ventilation. Housing block arrangement and surrounding are as important as an apartment house unit's design to predict the performance of the natural ventilation equipment. They should be carefully considered to make natural ventilation facilities functional.

국화 ‘백마’의 시설재배에서 야간 환기와 난방에 의한 상대습도 조절에 따른 흰녹병 발생과 생육

유용권(Yong Kweon Yoo),노용승(Yong Seung Roh),남병철(Byung Cheol Nam) 한국원예학회 2016 원예과학기술지 Vol.34 No.6

본 연구는 스탠다드 국화 ‘백마’의 시설재배에 있어서 야간 환기 방법과 난방처리 조건에 따른 온습도의 변화, 흰녹병 발생 및 절화의 생육에 미치는지 영향을 알아보고자 수행되었다. 환기 방법에 관한 실험에서 측창을 밀폐시킨 대조구의 평균 상대습도 94.5%에 비해 자연환기는 74.3%, 자연+Fan환기 처리구에서는 72.8%로 낮았다. 흰녹병 발생률은 대조구 100%, Fan환기 98.3%, 자연환기 75.6%, 자연+Fan환기 처리구에서 43.4%로 나타났다. 또한 발병엽수와 동포자퇴수도 다른 처리들보다 자연+Fan환기 처리는 가장 적었다. 대조구에서는 과습과 흰녹병 발생으로 절화의 생육이 크게 억제되었는데, 자연+Fan환기 처리구는 초장, 엽수, 줄기직경, 절화의 생체중 등 절화의 생육이 양호하였다. 난방 조건에 따른 시설 내의 야간 평균 온도는 대조구인 RH 95% 난방처리에서 18.4℃ 인데 반하여 RH 70% 난방처리에서 25.8℃ 로 나타나 7.4℃ 상승하였다. RH 70% 난방처리에서도 흰녹병 발생률 34.4%, 주당 발병엽수 0.9개, 발병엽당 동포자퇴수 1.0개로 대조구보다 흰녹병 발생이 크게 억제되었다. 또한 RH 70% 난방 처리구에서 습도가 높은 대조구보다 초장, 엽수, 줄기직경, 생체중 등 절화의 생육이 양호하였다. 따라서 시설 내에서 국화 ‘백마’를 재배시 자연+Fan환기와 난방처리는 흰녹병을 크게 억제할 수 있을 뿐만 아니라 절화의 생육에도 효과적이었다. This study was conducted to examine the effect of nighttime ventilation and heating on changes in temperature and humidity, the occurrence of white rust, and growth of standard chrysanthemum (Dendranthema grandiflorum) ‘Baekma’ in a greenhouse. For the ventilation treatments, the mean nighttime humidity in the control greenhouse, which had a closed side window, was higher (94.5%), but the humidity in the natural and natural+fan ventilation treatments was lower (74.3% and 72.8%, respectively). The rate of occurrence of white rust at 34 days after treatment was 100, 98.3, 75.6, and 43.3% for the control, fan ventilation, natural ventilation, and natural+fan ventilation treatments, respectively. The number of infected leaves and telia were the lowest in the natural+fan ventilation treatment compared with the other treatments. The growth of the chrysanthemum ‘Baekma’ was significantly suppressed in the control because of the occurrence of white rust and high humidity, while plant height, number of leaves, stem diameter, and fresh weight were the greatest in the natural+fan ventilation treatment. For the heating treatments, the mean nighttime temperature of the control (RH 95% heating), which was heating and held at 95% humidity, was 18.4℃, while the temperature of the heating treatment, which was held at 70% relative humidity (RH 70% heating) was 25.8℃. The rate of occurrence of white rust (34.4%), number of infected leaves (0.9), and telia (1.0) were the lowest in the RH 70% heating treatment compared with the other heating conditions. Also, the RH 70% heating treatment showed the best growth in terms of plant height, stem diameter, number of leaves, and fresh weight. Therefore, the natural+fan ventilation and RH 70% heating treatments were effective for the control of white rust and the growth of standard chrysanthemum ‘Baekma’ in a greenhouse.

결로방지를 위한 공용배기 활용 환기 시스템의 습도저감 성능 분석

이수인(Suin Lee),최경석(Gyeong-Seok Choi),이용준(Yong Jun Lee),이현화(Hyun-Hwa Lee) 대한설비공학회 2021 설비공학 논문집 Vol.33 No.2

In order to prevent condensation, it is necessary to remove water vapor through ventilation. In this study, we proposed a hybrid ventilation system in which natural ventilation and cen-tralized exhaust fan (VCE) ventilation systems are linked, and then compared the air flow of the natural ventilation system and the VCE system using a Computational fluid dynamics (CFD) model. The possibility of condensation was analyzed according to the systems’ chang-es in temperature and relative humidity, and the temperature and the humidity of the ventila-tion systems were directly measured within apartment houses. The results revealed that the ventilation volume of the whole household measured at 0.15 ACH when the natural ventila-tion was applied, and 0.50 ACH when the VCE system was applied. The average indoor air temperature only decreased by 1℃ when VCE was applied, indicating a very slight differ-ence when compared to the natural ventilation system. In addition, the result of analyzing the relative humidity distribution shows that the local relative humidity exceeded 100%, and that condensation conditions were formed when the natural ventilation system was applied. How-ever, the relative humidity distribution was even, and less than 100%, when the VCE system was applied, indicating a low probability of condensation. The results of analyzing the dif-ferences in average indoor air temperature with the VCE system shows that the air tempera-ture was measured to be 1.9℃ lower in the living room, and 2.27℃ lower in the laundry room, the balcony, and the evacuation space, than the air temperatures achieved with the nat-ural ventilation system. As a result of measuring the levels of absolute humidity, the average absolute humidity with the shared exhaust ventilation system was lower by 44.56% in the liv-ing room, the laundry room, and the evacuation space, when compared to the humidity of the natural ventilation opening case. Therefore, the results revealed that the humidity reduction performance was improved when the shared exhaust ventilation system was applied, when compared to the natural ventilation system, which could be effective in the prevention of condensation.

자연환기용 공장창호의 빗물유입 저감대책에 관한 실험적 연구

박승욱 ( Cheng Xu Piao ),김태형 ( Tae Hyeung Kim ),하현철 ( Hyun Chul Ha ),허영빈 ( Rong Bin Xu ) 한국산업위생학회 2010 한국산업보건학회지 Vol.20 No.3

Windows are widely used for natural ventilation of the various buildings. Especially high level windows as a part of industrial ventilation systems, play a crucial role in natural ventilation. Compared to mechanical ventilation system, natural ventilation has the advantage of lower installation and operating costs. In general, high level windows for industrial buildings have three types; louver type, 45° open type and 90° open type. Based on previous studies, it was found that the louver type and 45° open type are very effective in reducing rainwater penetration, but they did not have enough ventilation efficiencies. Preliminary tests were performed with the various types of windows. It was found that a 90˚ open double layer type window was the best among those which tested in our preliminary tests. Simulated rain was used to estimate the amount of rain penetrated through windows and to observe the paths of rain penetration. Various 90˚ open windows were tested to find the windows with minimum rain penetration and maximum ventilation efficiency.

Comparison of volume flow rate and volume-averaged local mean age of air for evaluating ventilation performance in natural ventilation

박진수,이광훈 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.12

Evaluating the ventilation performance is an important part of natural ventilation studies. We considered the volume flow rate, which is used by many researchers, and the volume-averaged Local mean age of air (LMA) as the ventilation performance parameters to evaluate the performance of natural ventilation. Computational fluid dynamics (CFD) simulations were performed on an isolated building model of cross ventilation that contained two openings on the windward and leeward wall and single-sided ventilation model that consisted of a single opening. Parametric studies were performed to evaluate the ventilation performance of eight different building configurations in cross ventilation and single-sided ventilation. Using the volume flow rate it was difficult to evaluate the ventilation performance when the inlet and outlet were very close in cross ventilation and, in single-sided ventilation, it was difficult to evaluate when the airflow speed was fast near the opening but did not penetrate inside the building. While the volume-averaged LMA was an adequate parameter for representing the ventilation performance of the building, the LMA field was a more accurate representation of the local ventilation performance inside the building than the velocity vector field.

공동주택에서 자연환기시스템의 적용성 검토

진재훈(Jae-Hoon Jin),송두삼(Doosam Song) 대한설비공학회 2010 대한설비공학회 학술발표대회논문집 Vol.2010 No.6

In most of the newly-built residential buildings in Korea, the mechanic ventilation system is mainly installed owing to the convenience of installation and the coincidence with a related ventilation standard. However, the operation rate of mechanical ventilation system is very low. As a result, through the Housing Performance Indicator System, it is imported hybrid ventilation system using both mechanical and natural ventilation. The one of the most important things of hybrid ventilation system design is to maximize the natural ventilation performance. Typically, the natural ventilation system is designed as same size without considering the wind environment of each household in multi-residential building block. This results in the difference of ventilation performance in each household because wind environment of each household in building block is varied with arrangement changes. The objective of this study is to analyze the feasibility of natural ventilation system into multi-residential buildings.

공기순환장치를 이용한 실내 환기성능 및 온열환경 개선에 대한 실험적 연구

이규남(Rhee, Kyu-Nam),정근주(Jung, Gun-Joo) 한국건축친환경설비학회 2018 한국건축친환경설비학회 논문집 Vol.12 No.3

Although natural ventilation is effective in improving indoor air quality in the intermediate season, its effect can be reduced if single-sided ventilation is applied to the room with much depth. In this case, interior zones can suffer from the insufficient ventilation rate, which can result in poor indoor air quality and occupants’ discomfort. This problem may be solved by implementing air circulators, which can diffuse the air in the perimeter zone into the entire space. In this context, the impact of air circulators on the ventilation performance and thermal environment was investigated through field measurement in a lecture room. Air circulators were combined with the mechanical ventilation (energy recovery ventilator) and natural ventilation. Measurement results showed that the air circulator can reduce CO₂ concentration by enhancing air diffusion in the entire space, when it is combined with the natural ventilation. In addition, it was found that the combination of air circulators and natural ventilation is effective in providing thermal comfort by increasing air speed, particularly during the intermediate season when the outdoor temperature is relatively high. It can be concluded that the air circulator can be utilized to supplement the single-sided natural ventilation for the room with much depth.

Experimental study on Venturi-type natural ventilator

Kim, Yeong Sik,Han, Dong Hun,Chung, Hanshik,Jeong, Hyomin,Choi, Soon-Ho Elsevier Sequoia S.A 2017 Energy and buildings Vol.139 No.-

<P><B>Abstract</B></P> <P>With the vigorous spread of renewable energy, much attention has been paid to natural ventilation. The natural ventilator is usually classified into a passive type and an active type. In this study, the Venturi-type ventilator, which is one of the passive type and basically operated by the Bernoulli’s principle, was experimentally investigated to evaluate the ventilation characteristics according to the outdoor wind velocities and the opening area of a wall. It was confirmed from the experimental results that the ventilation rate of the Venturi-type ventilator was linearly increased and that the ventilation rate was affected by an intake opening area. The wider the intake opening size gets, the more the ventilation rate increases. Furthermore, the new coefficient of β, which reflects the pressure loss from the intake opening to the mixing zone of the Venturi-type ventilator was introduced and experimentally evaluated. The value of β, which was evaluated as about 0.08, provides the simple calculation means to estimate the ventilation rate through the Venturi-type ventilator only if the geometric dimensions are known.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ventialtion rate measurements through Venturi-type natural ventilator. </LI> <LI> Area ratio effect (Intake opening area/Ventilator suction area) to ventilation rate. </LI> <LI> Saturation of ventilation rate over any fixed wind speed in a specific area ratio. </LI> <LI> Ventilation characteristics due to the wind velocity and the intake opening area. </LI> </UL> </P>

방음터널의 자연환기성능 향상에 대한 연구

이경희,조성우,최정민,김경환,박창섭 대한설비공학회 2005 설비공학 논문집 Vol.17 No.10

This paper compared ventilation performance between the sound roof tunnel with flat roof and the sound roof tunnel with gable roof. The ventilation rate of the sound roof tunnel is calculated by natural ventilation rate plus ventilation by vehicle. The roof type is divided by the shape of the roof and the ventilator location on the roof. The results between calculation and CFD on the ventilation rate are almost alike. The ventilation rate on the flat roof is 558.4m3/s with mid-ventilator and 496.8m3/s with left-right ventilator. The ventilation rate on the gable roof is 653.2m3/s with mid-ventilator and 611.6m3/s with left- right ventilator. The ventilation rate of soundproof with gable roof is higher than that with flat roof. The ventilation rate and with mid-ventilator is higher than that with left-right ventilator the soundproof roof. Therefore, the ventilation performance of soundproof roof depends on the roof shape and ventilator location on the roof.

연돌환기를 이용한 오피스빌딩 자연환기사례 연구

이아영(Lee, Ah-Young) 대한건축학회 2011 대한건축학회논문집 Vol.27 No.12

The purpose of this study was to investigate the natural ventilation methods using stack ventilation in offices. Natural ventilation is one of key factors to compose low energy and healthy buildings. Mechanical cooling and ventilation load can be dramatically reduced by natural ventilation and this is occurred by stack ventilation through solar chimney and atrium. The world famous sustainable office buildings to use stack ventilation were categorized into two types: “solar chimney” and “atrium”. The investigation shows that stack ventilation heavily relies on shading component and operable windows of exterior skin, precooling of intake air, location, height and materials of chimney and composition of atrium space. Finally, the space composition models for solar chimney and atrium are proposed based on the case analysis and the effectiveness of stack ventilation is verified by CFD simulation as the space composition is the basis for stack ventilation.