• Journal of The Korea Institute of Healthcare Architecture
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• v.8 no.1
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• pp.7-12
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• 2002

The air ventilation system of operation rooms has been studied to prevent the cross infection during the operation. Operation rooms and air ventilation systems of three University hospitals were investigated. The distribution of microbe was measured by cultivating air samples in the operation room. A two-dimensional model for the cross-section of an operation room was developed for the CFD(Computational Fluid Dynamics) analysis. The characteristics of air flow in the empty operation room and in occupied operation room were calculated by using a CFD program. The current diffuser location of an old hospital did not deliver the clean air to the operation part efficiently. A new method to locate diffusers that improve air venting with little increase of the cost of equipment was suggested.

• Journal of the Korean Society of Safety
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• v.21 no.2 s.74
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• pp.46-51
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• 2006

The smoke exhaust system is one of the effective systems to save lives when fire occurs underground. This study presents a complete analysis of effective smoke exhaust and smoke characteristics for a fire occurring with a transverse ventilation system use as a smoke exhaust system. The performance of the smoke management system was studied by computer modeling using FDS version 3.1. A fire size of 20MW was used for tunnel with balanced exhaust transverse ventilation. The smoke management design and the procedure as simulated in this study are also compliant to the tunnel construction and fire codes of Korea.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.5
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• pp.206-211
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• 2014

The objective of the present study was to identify ventilation problems, and also to suggest new axial fan systems for the improvement of IAQ in the underground parking lots. Numerical results for air mean-velocity, local mean age, and sound power level are presented along with some of fan angles. The results showed the influence of airflow patterns on the fan performances installed in the underground parking lots. Discharge air volume is increased with the angle of the blade. And also, the main factors affecting the noise of the ventilation fan was found to be a rotational speed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.5
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• pp.16-22
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• 2018

This study is about flow distribution in ventilation systems used in marine louvers. The flow analysis on a louver installed on the vent of a vessel results in the following conclusions: (a) as the velocity of the fluid entering the louver increases, the pressure drop increases; (b) as the pressure drop increases, it tends to increase following a quadratic function. The velocity was confirmed to decrease at the entrance of the louver. This indicates that as the pressure increases, the velocity decreases, and the velocity of the moving fluid is increasing as it passes through the louver vanes.

• Journal of Korean Tunnelling and Underground Space Association
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• v.13 no.6
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• pp.451-462
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• 2011

The smoke control system plays the most important role in securing evacuation environment when a fire occurs in road tunnels. Smoke control methods in road tunnels are classified into two categories which are longitudinal ventilation system and transverse ventilation system. In this study it is intended to review the characteristics of smoke behavior by performing numerical analysis for calculating the optimal smoke exhaust air volume with scaled-model and simulation when a fire occurs in tunnels in which transverse ventilation is applied, and for obtaining the basic data required for the design of smoke exhaust systems by deriving optimal smoke exhaust operational conditions for various conditions. As a result of this study, when the critical velocity in the tunnel is 1.75 m/s and 2.5 m/s, the optimal smoke exhaust air volume has to be more than $173m^3/s$, $236m^3/s$ for the distance of the smoke moving which can limit the distance to 250 m. In addition, in case of uniform exhaust the generated smoke is effectively taken away if the two exhaust holes near the fire region are opened at the same time.

• Journal of the Korean Society of Safety
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• v.15 no.1
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• pp.72-79
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• 2000

In recent, occupational diseases in harmful working places become a social issue. It is the well-known fact that a respiration in polluted working places exert a serious effect on health of workers. Accordingly, the cutting off contaminants air originally is the best way to improve working environments. In these cases, ventilation systems should be essentially installed to dilute or exhaust the contaminated indoor air. In this study, we investigated the characteristics of ventilation system of the noxious gas in working indoor places with natural ventilation by using COMET. The numerical simulations were carried out the natural ventilation with two phase(air, dust). For turbulent flow, Reynolds stresses were closed by the standard $\kappa$-$\varepsilon$ model. The results are as follows ; 1) In the natural exhaust in the working place, the flows of the central region have a more rapid velocity vector than the right and left one. 2) Numerical results show that the distribution of contaminants concentration have greater influence on convection than the case of diffusion by government of velocity vectors. 3) To observe the velocity variation with distance, three location of distance are considered. As results, it shows that the velocity are 0.075(m/s) at y=5(m), 10(m) and mean concentration are raised 10.6% at y=5(m), 10(m). 4) We have presented the useful data for the adequate counterplan in the harmful working places by carrying out the various investigation of the natural ventilation.

• Fashion & Textile Research Journal
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• v.16 no.3
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• pp.485-491
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• 2014

This study verified the effect of summer flight ventilation developed in a previous study based on wearing comfort evaluation. Seven healthy males in their twenties volunteered for this experiment conducted in aclimatic chamber. The experiment consisted of three consecutive periods of rest (20 minutes), running on a treadmill (10 minutes) and recovery (20 minutes). A comparative evaluation was conducted on the general flight suit which had no ventilation holes and summer flight suit that use subjective satisfaction measures and objective measures. The subjective satisfaction was evaluated according to the criteria of temperature sensation, wet sensation, thermal comfort and fatigue sensation. The objective satisfaction was measured by skin temperature, microclimate (temperature and humidity), sweat rate and thermography. The comparative wearing evaluation identified the summer flight suit decreased the temperature between skin and suit by $0.42^{\circ}C$ (upper arm), $0.9^{\circ}C$ (calf) and the skin temperature by $0.3^{\circ}C$ (shoulder), $0.4^{\circ}C$ (upper arm), $0.5^{\circ}C$ (calf) as compared to the general flight suit. The humidity inside the summer flight suit decreased at head (7.73%), shoulder (5.86%), upper arm (5.26%), and calf (8.73%) compared to the one inside the general flight suit. Thermography showed that the air flowed through ventilation holes (neck and armpit). The design of ventilation holes applied to the summer flight suit can be applicable to overall clothing that requires thermal comfort such as dust-free garments, mechanical clothing and combat uniforms.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.6
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• pp.1215-1220
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• 2019

Currently, each farm bears both the outbreak of foot-and-mouth disease and the damage caused by AI. In addition, complaints about odors in the livestock industry are constantly being recovered and are expected to occur in the future. The purpose of this study is to improve the indoor air quality of enclosed facilities such as barns, houses, pigsty, and etc. This paper develops low-temperature plasma waste heat ventilation system to be installed in ventilation unit location and standardizes heat exchange element, low-temperature plasma lamp, and ballast for enhanced air cleaning function. In addition, this study intends to develop a new control system so that the farmers can connect with existing weather systems, flow fans, and other facility equipment by incorporating ICT.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.3 no.2
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• pp.213-226
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• 1993

The purpose of this study is to computerize the design of single source for a duct work system which is essential for the improvement of working places. There are different types of hood, such as general hood, push pull hood and canopy hood. And out of these three types, general hood and canopy hood were used as subjects of this study. The software used here was Quattro Pro 123 programm, and the hardware was IBM PS/SX(type 5510-SK4 S/N 83-05164). And the results are tabulated in