• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2006년도 하계학술발표대회 논문집
• /
• pp.411-416
• /
• 2006

In this paper, we performed the experimental and numerical study on the thermal comfort(TC) and indoor air quality(IAQ) in the lecture room with a different airflow rate of the ventilation system and heating system for heating season. Through the experimental results, we found out that there was considerably difference of the PMV but there was little difference of $CO_2$ concentration with a different heating system. From a numerical results, the best operating condition was that discharge airflow rate of SAC is 29 CMM and supply airflow rate of the ventilation system is 1,200 CMH from a viewpoint of TC and IAQ.

• 한국환경과학회지
• /
• 제15권10호
• /
• pp.913-918
• /
• 2006

Despite the wide distribution of air pollutants, the concentrations of indoor air pollutants may be the dominant risk factor in personal exposure due to the fact that most people spend an average of 80% of their time in enclosed buildings. Researches for improvement of indoor air quality have been developed such as installation of air cleaning device, ventilation system, titanium dioxide$(TiO_2)$ coating and so on. However, it is difficult to evaluate the magnitude of improvement of indoor air quality in field study because indoor air quality can be affected by source generation, outdoor air level, ventilation, decay by reaction, temperature, humidity, mixing condition and so on. In this study, evaluation of reduction of formaldehyde and nitrogen dioxide emission rate in indoor environments by $TiO_2$ coating material was carried out using mass balance model in indoor environment. we proposed the evaluation method of magnitude of improvement in indoor air quality, considering outdoor level and ventilation. Since simple indoor concentration measurements could not properly evaluate the indoor air quality, outdoor level and ventilation should be considered when evaluate the indoor net quality.

• 한국연초학회지
• /
• 제21권1호
• /
• pp.102-108
• /
• 1999

This study was conducted to evaluate the ventilation to remove gases, vapor and particles of environmental tobacco smoke(ETS) in a closed room. The ventilation rate choosed were 0.445 ㎥/min, 0.528 ㎥/min, and 0.625 ㎥/min. ETS components measured were total suspended particle(TSP), ultraviolet particulate matter(UVPM), fluorescent particulate matter(FPM), solanesol, carbon dioxide($CO_2$), carbon monoxide(CO), nicotine, and 3-ethenylpyri-dine(3-EP). The concentration of ETS components measured rapidly decreased as increasing ventilation rate, but the removal efficiency by ventilation was different from each ETS compounds. The $CO_2$, and CO, gaseous components of ETS, were dominant components to be removed from the room by ventilation. The ventilation with 0.528 ㎥/min for 1 hr was enough to remove over 99% of those gaseous components. Nicotine and 3-EP needed the ventilation for 2 hrs to reduce over 95 % of those components. As the same ventilation rate, 99 % of TSP and solanesol concentration were removed from the room within 2 hrs, UVPM and FPM concentration decreased 90 %.

• 한국산업보건학회지
• /
• 제15권3호
• /
• pp.160-165
• /
• 2005

Schools have significant and serious indoor environmental health problem, of which indoor air quality (IAQ) in school building may affect the health of the students and indirectly affect learning performance. Schools are of special concern when regarding indoor exposure to air pollutants, because students are particularly sensitive to pollutants and spend a significant amount of time in that environment. Therefore researches for improvement of indoor air quality have been developed such as installation of air cleaning device, ventilation system, titanium dioxide(TiO2) coating and so on. However, it is difficult to evaluate the magnitude of improvement of indoor air quality in field study because indoor air quality can be affected by source generation, outdoor air level, ventilation, decay by reaction, temperature, humidity, mixing condition and so on. In this study, evaluation of reduction of formaldehyde emission rate in school indoor environments by far-Infrared ray coating material was carried out using mass balance model in indoor environment. we proposed the evaluation method of magnitude of improvement in indoor air quality, considering outdoor level and ventilation. Since simple indoor concentration measurements could not properly evaluate the indoor air quality, outdoor level and ventilation should be considered when evaluate the indoor air quality.

• 설비공학논문집
• /
• 제17권10호
• /
• pp.914-921
• /
• 2005

In this study, the 1/20 reduced-scale experiment using Froude scaling were conducted to investigate the effect of longitudinal ventilation velocity on the burning rate in tunnel fires. The methanol pool fires with heat release rate ranging from 2.02 kW to 6.15 kW and the n-heptane pool fires with heat release rate ranging from 2.23 kW to 15.6 kW were used. The burning rate of fuel was obtained by measuring the fuel mass at the load cell. The temperature distributions were observed by K-type thermocouples in order to investigate smoke movement. The ventilation velocity in the tested tunnel was controlled by inverter of the wind tunnel. In methanol pool fire, the increase in ventilation velocity reduces the burning rate. On the contrary in n-heptane pool fire, the increase in ventilation velocity induces large burning rate. The reason for above conflicting phenomena lies on the difference of burning rate. In methanol pool fire, the cooling effect outweighs the supply effect of oxygen to fire plume, and in n-heptane pool vice versa.

• KIEAE Journal
• /
• 제10권1호
• /
• pp.19-24
• /
• 2010

Modern people are spending most of time in interior area. Indoor air environmental problem is one of the most effective factors influenceable to human health. Furthermore, saving energy and making ventilation system for pleasant indoor environment are necessary when it is faced shortage of energy over the world. In our country's case, it is already imposed that required quantity of air ventilation in buildings is 0.7 times per hour on "The regulation on building engineering system". As on the rise of the interests about Indoor air environment, Heat and Carbon dioxide emissions from User's metabolism, activity, furniture, and construction materials etc. could be the causes of Indoor air pollution. If these materials stays in Indoor air for so long, it could directly influence the user's health condition with a disease. As of building's sterilization improved that raised more mechanical ventilation. It also leads much energy waste in a period of high price of fossil fuel. Therefore, the way that saves energy and effective control of indoor ventilation is urgently needed. So, this study places the purpose on validating volume of indoor ventilation and user's comfortable degree by comparison CO2 emission rate through changing floor temperature.

• 대한건축학회논문집:구조계
• /
• 제35권10호
• /
• pp.235-243
• /
• 2019

In South Korea, millions of poultry have died due to repeated heat waves every year. The purpose of this study is to analyze the characteristics of heating and cooling loads of chicken houses in Korea and to present an effective insulation and ventilation measures to minimize the damage of poultry due to summer heat wave and to save energy in chicken houses in winter. The heating and cooling loads of standard chicken house were calculated. As a result of the calculation of maximum heating load based on the minimum ventilation rate in winter, the outdoor air temperature requiring heating was $6{\sim}7^{\circ}C$ to keep the indoor air temperature of chicken houses as $24^{\circ}C$. The peak cooling load of chicken houses was mostly taken by the heat generated by chickens and the heat gain due to ventilation. The heat gain through building envelopes was as small as neglectable. Most of chicken houses is usually cooled by gigantic forced ventilation in summer in Korea. When the chicken houses are cooled by electric cooling machine such as cooler or air conditioner, it is more effective to keep minimum ventilation rate to reduce the maximum cooling load. To lower the temperature of supplying water to cooling pad, it is recommended to use the underground water below 10 meters from the ground if there is abundant underground water.

• 한국입자에어로졸학회지
• /
• 제19권2호
• /
• pp.43-53
• /
• 2023

In this study, the ventilation system of the enclosed conveyor belt for coal transportation was evaluated, and the particle removal efficiency according to the ventilation conditions was identified using computational fluid dynamics and particle behavior analysis. The most effective way to remove dust generated inside the closed conveyor belt is to adjust the position of the exhaust port of the duct so that the air is exhausted around the rear of the conveyor belt. And this method seems to work for another narrow and long spaces where air enters in one direction. In addition, when the air flow rate of the each duct was less than 300 CMM, it was efficient to increase the flow rate of the duct located at the rear of the conveyor belt, and when the flow rate of the each duct was higher than 300 CMM, it was efficient to increase the flow rate of the duct located at the front of the conveyor belt.

• 한국환경보건학회지
• /
• 제33권2호
• /
• pp.92-97
• /
• 2007

A series of source tests were conducted to characterize emissions of nitrogen oxide(NOx, NO, $NO_2$), carbon mon oxide(CO), carbon dioxide$(CO_2)$ and total VOCs from portable combustion devices in steady-state using well-mixed chamber. Since use of portable gas range is widespread in houses and restaurants in Korea, it is important to characterize the emission of air pollutants and suggest optimum ventilation rate. Ranges of emission rates of air pollutants from portable gas ranges were $NO \;0.551\sim0.939mg/hr,\;NO_2\;0.354\sim1.080mg/hr,\;NO_x\;1.207\sim1.631mg/hr,\;CO\;1.389\sim4.21mg/hr,\;CO_2\;2426.823\sim2973.495mg/hr$, and VOCs $0\sim0.119mg/h$. Mean of personal exposure and indoor environment level of $NO_2$ by combustion of portable gas range were 74.7 ppb and 65.4 ppb, respectively, suggesting persons using portable gas range in houses and restaurants might be highly exposed. Required ventilation rate to control the air pollutants emitted from portable gas range was maximumly $3.131m^3/hr$ on the basis of $NO_2$ indoor air quality standard.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2005년도 동계학술발표대회 논문집
• /
• pp.33-38
• /
• 2005

A hybrid ventilation system was introduced to predict the ventilation performance of the apartments. This ventilation system was composed of the natural supply-air inlet and the forced exhaust-air outlet. Analysis was conducted by CFD technique and was performed on three ventilating flow rates; 30, 60, 120 $m^3/h$. As the results, residents feel comfortable thermally and in air flow conditions for 60 $m^3/h$. But the case of 30 $m^3/h$ shows 1100ppm of $CO_2$ concentration due to the deficient of air flow rate. In the case of 120 $m^3/h$, however, residents feel uncomfortable thermally and in air currents. In this study the energy saving for space heating is also an important factor. A detailed prediction for more complicated whole apartment space will be investigated in the future.