• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.12
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• pp.628-637
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• 2017

This study was conducted to present an effective control method for the common duct system to uniformly discharge volume flow rate exhausted from the kitchen and bathroom of each household in an apartment regardless of the position of household. Since the common duct system is installed vertically and the ventilator is installed in the terminal, the static pressure of each household decreases when vertical height increases. Therefore, the volume flow rate exhausted from each household is different. In order to improve such a phenomenon, a constant air volume damper shall be installed in a branch duct coupled with a common vertical duct system. The selected ventilator should also be able to handle the maximum volume flow rate considering diversity factor. Therefore, a uniform volume flow rate must be exhausted from all households where the hood is operated. This paper mainly focuses on suggestion of an optimum exhaust control method by comparing exhaust performance of each household according to the presence or absence of a constant air volume damper.

• Journal of Environmental Science International
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• v.8 no.1
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• pp.27-32
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• 1999

This study identified concentrations of all pollutants emitted from idling of vehicles such as cars, taxis, trucks, and buses. In this investigation we analyzed concentrations of $SO_2$, NOx, CO, and $CO_2$ omitted from exhaust pipe of vehicles as a function of vehicle type, mileage, exhaust volume, and fuel type using the GreenLine. Compact or light cars, which have relatively low exhaust volume, showed much higher exhaust concentrations of $CO_2$, CO, and NOx than those emitted from vehicles with high exhaust volume. Vehicles using light oil showed much higher exhaust NOx concentrations than those of vehicles using gasoline. Vehicles using LPG and compact cars showed very high exhaust CO concentration compared to other vehicles. NOx exhaust concentrations were increased with increasing the mileage of vehicles.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.3
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• pp.186-192
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• 2009

In this study it is intended to review the moving characteristics of smoke by performing visualization for calculation of the optimal smoke exhaust air volume in case a fire occurs in tunnels where transverse ventilation is applied, and to obtain basic data necessary for design of the smoke exhaust systems by deriving optimal smoke exhaust operational conditions under various conditions. As a result of this study, if it was assumed 0 critical velocity in the tunnel, the smoke exhaust air volume was limited within 250 meter in the road-tunnel disaster prevention indicator and the exhaust efficiency was from 55.1% to 95.8% in the result of this study. In case of oversized exhaust ports, the generated smoke is more than the case of uniform exhaust. 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 $173\;m^3/s$, $236\;m^3/s$ for the distance of the moving smoke which can limit the distance to 250 m.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.4
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• pp.394-404
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• 2020

Objectives: The aims of this study are to derive the characteristics of diesel exhaust gas emissions generated during vehicle checking in the garage of fire stations and of the related improvement plans for proper air quality management. Methods: The researcher measured changes in the air quality inside garages according to the operating conditions of the exhaust facility and before and after vehicle checking at three fire stations. Results: During the checking of fire engines, a large volume of hazardous substances exceeding management standards were generated, and improvement of the discharge facilities was required for proper air quality management. Conclusions: It is necessary to study the hazard evaluation of firefighters' exposure to exhaust gas, to operate exhaust gas ventilation facilities, and to prepare technical standards for proper indoor air quality management.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.1
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• pp.40-49
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• 2000

The flow and heat transfer characteristics of the exhaust airflow window system were studied numerically by a finite volume method. Attention was paid to see the decrease in indoor cooling load. The exhaust air flow rate, solar energy power and aspect ratio of window were considered as main variables. From the result of the comparison between the exhaust airflow window and the enclosed window, the indoor heat gain was reduced remarkably by 76%. It is also suggested that in the design of the exhaust airflow window optimum values of aspect ratio, H/W and exhaust air flow rate, Re were about 0.05 and 600, respectively.

• 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.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1244-1250
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• 2009

In this study it is intended to review the moving characteristics of smoke by performing visualization for the calculation of the optimal smoke exhaust air volume in case a fire occurs in tunnels where transverse ventilation is applied, and to obtain basic data necessary for the design of smoke exhaust systems by deriving optimal smoke exhaust operational conditions under 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 $173\;m^3/s$, $236\;m^3/s$ for the distance of the smoke moving which can limit the distance to 250m. 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.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.2
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• pp.1-8
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• 2004

A cylindrical constant volume combustion chamber was used to investigate the exhaust emission characteristics of homogeneous charge, stratified pattern and inhomogeneous charge under various conditions using gas chromatography. In the case of homogeneous charge condition, the $CO_2$ concentration is proportional to excess air ratio and overall charge pressure, the $CO_2$ concentration is proportional to excess air ratio and the UHC concentration is inversely proportional to ignition time and overall charge pressure. In the case of stratified pattern, the RI(rich injection) condition shows better exhaust emission characteristics, especially $CO_2$, than that of HI (homogeneous injection) or LI (lean injection) conditions. In inhomogeneous charge conditions, when initial charge pressure is increased, $CO_2$ and UHC concentration is reduced but $O_2$ concentration is increased. And when the excess air ratio of initial charge mixture is 3.0, UHC and $CO_2$concentration show lowest values.

• KIEAE Journal
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• v.17 no.5
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• pp.43-50
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• 2017

Purpose: Residential cooking(gas or electricity) emits many air pollutants. For Removal of these contaminants, range hood is play an important role in the cooking activities. However, deterioration about performance of range hood can be occur in used range hood which is not verified on performance by testing balancing and adjusting in apartment. So, purpose of this study is to improve the range hood against cooking-generated contaminations. Method: To improve hood, survey of range hood which mounted in apartment have to conduct at first. In this study, the survey was conducted for 3 steps. First, Visual inspection for conditions of range hood. Second, questionnaire of operating and maintenance method. Third, interview with user about need for improvement, complainant. Finally, we integrated the survey for range hood and introduced the probable cause of deterioration through this comprehensive survey. Result: Result of measurement for air volume for range hood, A measured air volume has reduced by 41.4, 38.0, 32.0% each step from rated air volume. There are lots of reasons of this phenomenon including to maintenance, air path of duct, lower-cost devices, exhaust ports. For solve this problem, guideline about operating hood, user in apartment will have to supply with maintenance information at first.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.2
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• pp.136-141
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• 2012

Performance improvement of local exhaust system used in toilet and cooking place are main concern in a field of ventilation. In Korea, There are many high riser residential apartments in recent years. These buildings were not viewed as being major contributors to exhaust pollutants producted in indoor. It was because many engineers thought that exhaust in high riser building depends on stack effect. This study investigates on the performance improvement of terminal device, roof fan, of vertical spiral duct used in high riser residential apartments. This paper focuses mainly on the effect of accessories, number or shape of blades, composed of roof fan with function of exhaust air volume of toilet and cooking place. Roof fan with 10 blades is observed at optimum exhaust performance in this study.