• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.523-528
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• 2008

The accurate distribution of flow rate has been a very important part to control the air change rate since introduction of house ventilation system. An inappropriate selection of fan due to incorrect prediction of pressure loss in duct brings energy loss. In the previous study the pressure loss of general spiral duct was measured and database was constructed for finding correct loss factors in fitting upper stream. The purpose of this study is to compare and investigate the error range of flow rate by applying T-Method to bilateral symmetry and asymmetry layout of duct. The results of this study are as following. It is demanded to decide accurate size under duct design for house ventilation system. Because the small amount of Flow rate was considered at that time. The error range was 3.17% on case1 and 3.52% on case2. The error range difference was 0.35%.

• Journal of Biosystems Engineering
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• v.34 no.1
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• pp.63-68
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• 2009

This study was carried out to determine necessary conditions for optimal ventilation of small windowless piglet house (5.2 (W) ${\times}$ 12.3 (L) ${\times}$ 2.3 (H) m) with negative tunnel ventilating system using CFD (Computational Fluid Dynamics) simulation. The weaning piglet house for this experiment was consisted of 4 rooms (520 (W) ${\times}$ 300 (L) cm), 3 fences (70 (H) cm), 1 air inlet (350 (W) ${\times}$ 2 (H) cm) and 1 exhaust fan (50 (D) cm), and simulated using CFD code, FLUENT. The simulation results for the original weaning piglet house showed ununiform ventilation for each room. Therefore, to uniformly ventilate all rooms, the heights of the air inlet and first fence were modified to 3 cm and 100 cm, respectively. The simulation result f3r the modified weaning piglet house showed uniform ventilation for all rooms and the optimum air inlet velocity of 1.4 m/s.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2002.11a
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• pp.315-320
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• 2002

Marketing ventilation fan 3 kinds been using in kitchen of apartment house into compensation discharge performance of contaminant measure. When propane gas burns by gas table, did waste heat into measurement compensation with carbon dioxide that it happens. In measured all type of exhaust fan, discharge performance of carbon dioxide and waste heat was high there are been much displacement. Among A, B, C three types, performance of A type exhaust fan was most superior and performance of C type exhaust fan was most poor

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.8
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• pp.649-655
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• 2006

The recent indoor air quality problem in a newly-built apartment house is resulted from the improvement of airtightness performance and the use of the building material contained harmful chemical substances. As a result, these cause indoor air quality gradually to become worse and the harmful effect on occupant health called Sick House Syndrome. The most effective solution to improve the indoor air quality is to encourage the use of green building material. However, if the house is built with general building material, ventilation with outdoor air is alternative to dilute the pollutant concentration. The purpose of this re-search is to find optimum ventilation time in a newly-built apartment house at which the ventilatoris installed. It is found that the HCHO and toluene concentrations are remarkably decreased with the elapse of ventilation time and the concentration reduction rate is increased with increment of air change rate after one hour after operating the ventilator.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.2
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• pp.55-65
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• 2012

In the winter season, when the ventilation system is operating, the fresh cold air from the slot-type openings of broiler house which directly reached the animal zone can cause various problems such as thermal stress, decreasing of feed and water consumption, occurrence of respiratory disease, and etc. Therefore it is very important to control the trajectory of aero-flow from the slot openings to induce an efficient thermal heat change. Jet-drop distance model was proposed to predict and control the jet-trajectory. However their study was restricted due to the small scaled model and difficulties of measuring the Jet-drop distance. In this study, CFD was applied to analyze qualitatively and quantitatively the jet-drop distance in a real broiler house. The various variables were considered such as installed slot-angle, designed ventilation rate, and the outdoor ambient temperature. From the present study, two linear-regression models using the Jet-drop factor and corrected Archimedes number, and their R-squared values 0.744 and 0.736, respectively, were used. From this study, the applicability of CFD on the analysis of Jet-drop distance model was confirmed.

• Land and Housing Review
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• v.6 no.4
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• pp.215-220
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• 2015

The purpose of this study was to comparative analyses of energy performance in apartment houses adopted window frame-type natural ventilation, under-floor air distribution ventilation and heat recovery ventilation. As the object of energy simulation, the three type ventilation system with area of $84m^2$ was selected in apartment house. As a result, when the ECO2 simulation was performed, the 1st requirement quantity per annual were $159.9kWh/m^2yr$(CASE1, Natural Ventilation), $179.7kWh/m^2yr$(CASE2, Under-floor Air Distribution Ventilation) and $161.0kWh/m^2yr$(CASE3, Heat Recovery Ventilation).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.7
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• pp.688-693
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• 2005

Nowaday the natural ventilation rate decreases because the apartment housing is being air-tight. Therefore, Indoor Air Quality (IAQ) and indoor environment grow worse. Especially, Formaldehyde (HCHO), Volatile Organic Compounds (VOCs) which is emitted from the building materials and coating material etc. occur Sick House Syndrome that cause negative impact on resident's respiratory system and body. Therefore in construction field, it will be a important issues that development of a ventilation system with high effectiveness which can exhaust the contaminant out of the building quickly. In this research we evaluated 'wall attachable duct-less Heat Recovery Ventilation (HRV) system with air cleaning function'. We executed a synthetic evaluation about indoor air environment under various operating condition installing the system in real scale apartment house that is built in Anyang city. HRV system with air cleaning function showed good performance by removing HCHO, VOCs with less ventilation energy.

• Journal of Biosystems Engineering
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• v.28 no.3
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• pp.225-230
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• 2003

This study was carried out to analyze the environmental variation of layer house at Iowa State in the USA. The analyzed seasons for this study were summer and winter. Analyzing factors are inside temperature and relative humidity, carbon dioxide concentration, ammonia concentration and emission. All factors were collected every 30 second from each house with portable monitoring units. In this study, two types of laying hen houses were monitored at the same season. One was a manure belt house, the other was a high-rise house. In order to estimate the ventilation rates of the laying hen houses, carbon dioxide concentration balance was used in this study. Ammonia concentrations and emission rates of the manure belt house are much lower than those of the high rise house. Daily mean ammonia concentrations in the manure belt house and high-rise house ranged from 3 to 7 ppm and 5 to 34 ppm, respectively. The daily ammonia emission rates averaged 0.68g/h$\cdot$500kg and 0.73g/h$\cdot$500kg for the manure belt house and 0.93g/h$\cdot$500kg and 2.89g/h$\cdot$500kg for the high-rise house in summertime and wintertime, respectively. Summertime is associated with much higher ammonia emission rates than wintertime because of much higher ventilation rates and ambient air temperature, even though the concentrations may be lower.

• Journal of Animal Science and Technology
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• v.44 no.1
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• pp.135-144
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• 2002

An experiment was conducted to evaluate a ventilation system, which was devised to encourage farmers to use the enclosed growing and finishing pig housing system. A roof-air-entry ventilation system in winter and a side-wall-air-entry system in summer were evaluated. Air flow rate on the floor level which is the low part of pen and the living area of pigs in the enclosed growing and finishing pig house during winter was measured at 0 to 0.19 m/s at the minimum ventilation efficiency of 1,440 $m^{3}/h$. During summer the air flow rate was detected at 0.07 to 0.42 m/s at the maximum ventilation efficiency of 24,000 $m^{3}/h$. Therefore, it is concluded that the side-wall ventilation system is suitable for growing and finishing pigs in the enclosed house during the days of mid-summer and the roof-ventilation system was suitable during the coldest days of mid-winter. In addition, although the enclosed pig house has the system in which air exhausts through only one side wall, air should enter through both-side walls for the better ventilation performance.

• Korean Institute of Interior Design Journal
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• v.15 no.4 s.57
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• pp.129-137
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• 2006

The purpose of this study was to identify the influence of living factors on TVOC(Total Volatile Organic Compounds) concentrations and personal factors to reduce the Sick House Syndrome for newly-built apartments. The field measurements of TVOC concentrations were made totally 30 times(5 times per one subject house) in six apartment units in which residents recently moved. Those apartments authorized its business approval before May 2004, the Act of Indoor Air Quality Management for multi-use facilities. The Questionnaire surveys of residents' subjective responses on the Sick House Syndrome were carried out in 2nd measurement of each house. Respondents consisted of 20 residents living in the measured houses. The findings were as follows: The TVOC concentrations of the measured subject apartments ranged from about 1/10 of the recommended standard for multi-use facilities($400{\mu}g/m^3$) to up to 90 times as high as the standard. Since then, the Recommended Standard of Indoor Air Quality Management for newly-built apartment house was announced in December 2005. In accordance with this standard($2390{\mu}g/m^3$) it ranged from about 1/100 to up to 15 times as high as the standard. The subject house whose TVOC concentrations reduced below the recommendation standard in the shortest period had the largest amount of ventilation (all the windows were open for ventilation in the past three months) among all measured houses. The reason of another house whose TVOC concentrations were much higher than the rest was fronted with new furniture in the room. There turned out to be no apparent relations between the TVOC concentrations and the residents' individual responses of Sick House Syndrome. The responses were serious in those who stayed in their new houses for a long period or had disease like allergy. It's recommended that they should open all the windows for at least three months for ventilation in newly-built houses, and it would be better to avoid remodeling than needs be.