• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.429-433
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• 1999

The experiment was conducted to predict air movements and to analyzxe the ventilation characteristics in ventilated greenhouse. Relatively high wind velocity was checked near windward inlet, but near leeward outlet and indoor very low wind velocity near to zero was checked . Despite of much influent air, indoor temperature was watched as high values uniformly due to inadequate air flow in greenhouse and low ventilation efficiency of the greenhouse.

• 한국전산유체공학회:학술대회논문집
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• 2003.10a
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• pp.207-208
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• 2003

Increasing interest in indoor air quality (IAQ) control has been found because of its serious effect on human health. To evaluate IAQ, thermal comfort in terms of temperature and velocity distributions of indoor air has to be analyzed in detail. Choice of location for installation of air-conditioner in a building will affect the performance of cooling effect and thermal comfort on the occupants, which in turn will affect the indoor air quality (IAQ) of the building. In this paper, we present a discussion on the proper location of the air-conditioner in order to obtain good thermal comfort for occupant of a typical bedroom in Macao. A set of carefully designed numerical experiments is run with the Computational Fluid Dynamics (CFD) software FLOVENT 3.2 [1]. Reynolds averaged Navier-Stokes equations are solved with finite volume technique and turbulence effects upon the mean flow characteristics is modeled with the k - & model. Assumption of steady state environment is made and only convective and conductive heat transfer from the occupant and air-conditioner are being concerned.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.434-439
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• 2008

Dome stadiums give thermal unpleasant feeling to occupants because of the radiant heat and the indoor and outdoor haet exchange from roogs or lightweight building envelopes of sidewalls. This study analyzed the indoor temperature and velocity distribution according to various air supply and return sustems in dome stadiums in summer.

• International Journal of High-Rise Buildings
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• v.12 no.2
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• pp.129-136
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• 2023

Natural ventilation has proven to be an effective passive strategy in improving energy efficiency and providing healthy environments. However, such a strategy has not been commonly adopted to tall office buildings that traditionally rely on single-skin façades (SSFs), due to the high wind pressure that creates excessive air velocities and occupant discomfort at upper floors. Double-skin façades (DSFs) can provide an opportunity to facilitate natural ventilation in tall office buildings, as the fundamental components such as the additional skin and openings create a buffer to regulate the direct impact of wind pressure and the airflow around the buildings. This study investigates the impact of modified multi-story type DSFs on indoor airflow in a 60-story, 780-foot (238 m) naturally ventilated tall office building under isothermal conditions. Thus, the performance of wind effect related components was assessed based on the criteria (e.g., air velocity and airflow distribution), particularly with respect to opening size. Computational fluid dynamics (CFD) was utilized to simulate outdoor airflow around the tall office building, and indoor airflow at multiple heights in case of various DSF opening configurations. The simulation results indicate that the outer skin opening is the more influential parameter than the inner skin opening on the indoor airflow behavior. On the other hand, the variations of inner skin opening size help improve the indoor airflow with respect to the desired air velocity and airflow distribution. Despite some vortexes observed in the indoor spaces, cross ventilation can occur as positive pressure on the windward side and negative pressure on the other sides generate productive pressure differential. The results also demonstrate that DSFs with smaller openings suitably reduce not only the impact of wind pressure, but also the concentration of high air velocity near the windows on the windward side, compared to SSFs. Further insight on indoor airflow behaviors depending on DSF opening configurations leads to a better understanding of the DSF design strategies for effective natural ventilation in tall office buildings.

• International Journal of Air-Conditioning and Refrigeration
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• v.9 no.1
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• pp.71-76
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• 2001

Factors governing the rate of heat exchange comprise temperature, air velocity, relative humidity, and relation indoors. Recently, there are many researches on the transient analysis of indoor environmental factors such as dry bulb temperature, relative humidity and air velocity in miniature models. The purpose of this study is to measure the environmental factors and to analyze and evaluate the characteristics of indoor environment in different envelop structures using granite dome models. The interior relative humidity is constant regardless of exterior humidity although a little range of variation is shown in comparison to the cement model.

• Journal of the Korean Society for Railway
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• v.6 no.1
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• pp.41-48
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• 2003

Most of people spends their times in indoor about 85% of a day. Thus, indoor is more serious than outdoor concerned with the health. We discussed comfortableness in a railroad electric rolling stock, and focused on temperature and humidity. Electric rolling stock is one of major public transportation system because of an increasing in population and heavy traffic problems. The passengers are under the influence of indoor air quality such as air temperature, relative humidity and air velocity. Ventilation system in electric rolling stock should be designed for the health and comfort. One of the main aims is to create an acceptable thermal environment without draught problem. The draught sensation increases when the air temperature decreases and the air velocity increases. Airflow in electric rolling stork is turbulent. Temperature and humidity gradients in electric rolling stock have been studied. And, the difference between mean temperature and rotative humidity measured at 0.7, 0.9, 1.2, 1.7m above the floor. It has been found that temperature and relative humidity with large fluctuations caused more draught complaints.

• Journal of the Korean Solar Energy Society
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• v.34 no.1
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• pp.72-80
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• 2014

This study proposed a wind power generation system utilizing outdoor air on the rooftop and indoor ventilation, which would increase according to the building height, as a way to help to save energy consumption in a building by using wind power energy of the new renewable energy sources. The study measured the distribution of air currents and power generation according to the usage factor of exhaust pipes in the kitchen and bathroom and identified the elements to consider when applying a wind power generation system to buildings in order to use outdoor air on the rooftop increasing according to the height and the indoor ventilation produced in the facility vertical shafts inside the buildings by installing a wind power generation system on the rooftop. (1) The study measured the ventilation velocity of the kitchen hood and bathroom ventilation fan by changing the zone areas by the households according to the usage factor of [${\alpha}$]=33~100%. As a result, the kitchen ventilation pipe generated the ventilation wind of 3.0m/s or more at the usage factor of [${\alpha}$] 66% or higher, and the bathroom ventilation pipe generated ventilation velocity lower than 3.0m/s, the blade velocity of the wind power generator, even after the usage factor rose to [${\alpha}$]=100%. (2) As the old bathroom ventilation pipe generated the ventilation velocity of 3.0m/s, the blade velocity of the wind power generator, even with the rising usage factor [${\alpha}$], the application of an outdoor air induction module increased the ventilation velocity by 2.9m/s at the usage factor of [${\alpha}$]=33%, 3.8m/s at the usage factor of [${\alpha}$]=66%, and 3.6m/s at the usage factor of [${\alpha}$]=100%. Thus the ventilation velocity of 3.0m/s, the blade velocity of the wind power generator, or higher was secured. (3) The findings prove that the applicability of a wind power generation system using outdoor air on the rooftop and indoor ventilation is excellent, which raises a need for various efforts to increase the possibility of its commercialization such as securing its structural stability according to momentary gusts on the rooftop and typhoons in summer and making the structure light to react to the wind directions of outdoor air on the rooftop according to the seasons.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.4
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• pp.325-336
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• 2000

During the last decade, an increasing interest in Underfloor Air-Conditioning(UFAC) systems has emerged. The purpose of this paper is to evaluate comprehensively the indoor environmental performance of office buildings with UFAC system in order to develope the design prototype of this system. In this paper, the physical measurements and the interviewing survey of occupant's sensation responses to the environment were carried out. Measurements and survey were made of the thermal environmental factors such as air temperature, relative humidity, air velocity, globe temperature, and the other several environmental factors such as the sound level and the illuminance of working plane, etc. And, the air quality was evaluated by measuring the concentration of suspended particles, carbon monoxide, and carbon dioxide in the room. Furthermore, the paper appraises the various indoor environmental factors of the room by using post-occupancy evaluation(POE) method in office building with UFAC system, and thus, it suggests the basic data for assessing the indoor comfort based on field measurements and survey.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1330-1335
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• 2007

The HVAC and the air duct is to make optimal indoor environment. By the HVAC position, method and the air duct construction, the important elements can affect on cooling performance, passengers' convenience, and energy efficiency. According to this, there are features, such as the indoor temperature distribution, cooling performance, velocity distribution from diffuser, tend to be come out variously. Also, comparing and analysing temperature distribution, cooling performance, air velocity, noise based on the real practical vehicle tests, it shows features in detail. Besides, it can lead to make design the system of HVAC & air duct effectively.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.82-87
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• 2005

The characteristics of train-wind in the underground shopping center(UGSC) connected to subway station is investigated by field measurement for the case of train movement such as arrival and departure, etc. Also air curtain installed at the pass way between underground shopping center and subway station were considered as the parameter in order to analysis the effect on indoor air quality and thermal condition. The measurement data such as velocity, relative humidity, wind-pressure were plotted as quantity variation with time scale. The train-wind affected wind velocity, air pressure and relative humidity at the connecting area of underground shopping center and subway station, and the variation was about 4.5 m/s, 8%, 40 Pa. Also the result showed that the air curtain is not proper to reduce influence of train-wind