• Title/Summary/Keyword: Air source

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A Study on the Airflow near the Cold Heat Source Using CFD in Merchandising Store (CFD를 이용한 대형매장 냉열원 주변의 공기유동에 관한 연구)

  • Cho Sung Woo;Park Min Young;Im Young Bin
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.17 no.7
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    • pp.629-634
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    • 2005
  • This paper performed to predict vertical temperature distribution and air flow near cold heat source in the mass merchandising store. At the height of 150 cm, the vertical air temperature difference between the results of CFD and of measurement field showed $10\%$ near the refrigeration zone and $8.8\%$ near the freezing zone. Therefore, it regarded as appropriate for the using CFD to investigate airflow near the heat sources. The 3 kinds of CFD model were divided by the disposition of diffuser/exhaust and diffuser air temperature. At the refrigeration and freezing zone in the Model 2 and 3, the temperature difference between the front and the back of human model were showed $6.8^{\circ}C\;and\;3.9^{\circ}C$ with diffuser air temperature $17^{\circ}C$ and were showed $6.8^{\circ}C$ and $4^{\circ}C$ with diffuser air temperature $19^{\circ}C$.

Heating Effect of Greenhouse Cultivated Mangos by Heat Pump System using Underground Air as Heat Source (지하공기 이용 히트펌프시스템의 망고온실 난방효과)

  • Kang, Younkoo;Kim, Younghwa;Ryou, Youngsun;Kim, Jongkoo;Jang, Jaekyoung;Lee, Hyoungmo
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.200.1-200.1
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    • 2011
  • Underground air is a special energy source in Jeju and distributes lava cave, pyroclastic, open joint, and crushing zone. A possible area to utilize underground air is 85% of Jeju except to the nearby area of Sambang Mt. and 25m high coastal area from sea level. In Jeju, underground air is used for heating agricultural facilities such as greenhouse cultivated mangos, Hallbong and mandarin orange, pigsty, mushroom cultivation house, etc. and fertilizing natural $CO_2$ gas by suppling directly into agricultural facilities. But this heating method causes several problem because the underground air has over 90% relative humidity and is inadequate in heating for crops. Mangos are the most widely grown tropical fruit trees and have been cultivated since 1993 in Jeju. In Jeju, the cultivating area is about 20ha and amount of harvest is 275ton/year in 2010. In this study, the heat pump system using underground air as heat source was installed in mangos greenhouse which area is $495m^2$. The capacity of heat pump system and heat storage tank was 10RT, 5ton respectively and heating effect and heating performance of the system were analysed.

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Experimental Study on Heating Performance Characteristics of Air Source Heat Pump with Air to Water Type (공기열원 히트펌프의 난방 성능특성에 관한 실험적 연구)

  • Lee, Kwon-Jae;Kwon, Young-Chul;Chun, Chong-Keun;Park, Sam-Jin;Kwon, Jeong-Tae;Huh, Cheol
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.23 no.6
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    • pp.400-405
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    • 2011
  • This paper presents the heating performance characteristics of the air source heat pump with air to water type. The heating capacity, COP, P-h diagram were measured at various operating conditions, air-side temperatures, relative humidities, and inlet/outlet water temperature under the standard heating condition of KS B 6275. The experimental data for the heat pump were measured using the air-enthalpy calorimeter and the constant temperature water bath. As the air-side temperature increases, the heating capacity and COP increase. The effect of the air-side relative humidities on the heat pump performance is insignificant. The heat pump performance on inlet and outlet water temperatures and air-side temperatures(-7, -11, $-15^{\circ}C$) were studied. Heating capacity and COP increased about 27~39% with the air-side temperature increasing. Enthalpy between the front and the rear of condenser decreased about 6% by increasing of the inlet water temperature. These results can be utilized in the design of the air source heat pump system with air to water type.

Korea Emissions Inventory Processing Using the US EPA's SMOKE System

  • Kim, Soon-Tae;Moon, Nan-Kyoung;Byun, Dae-Won W.
    • Asian Journal of Atmospheric Environment
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    • v.2 no.1
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    • pp.34-46
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    • 2008
  • Emissions inputs for use in air quality modeling of Korea were generated with the emissions inventory data from the National Institute of Environmental Research (NIER), maintained under the Clean Air Policy Support System (CAPSS) database. Source Classification Codes (SCC) in the Korea emissions inventory were adapted to use with the U.S. EPA's Sparse Matrix Operator Kernel Emissions (SMOKE) by finding the best-matching SMOKE default SCCs for the chemical speciation and temporal allocation. A set of 19 surrogate spatial allocation factors for South Korea were developed utilizing the Multi-scale Integrated Modeling System (MIMS) Spatial Allocator and Korean GIS databases. The mobile and area source emissions data, after temporal allocation, show typical sinusoidal diurnal variations with high peaks during daytime, while point source emissions show weak diurnal variations. The model-ready emissions are speciated for the carbon bond version 4 (CB-4) chemical mechanism. Volatile organic carbon (VOC) emissions from painting related industries in area source category significantly contribute to TOL (Toluene) and XYL (Xylene) emissions. ETH (Ethylene) emissions are largely contributed from point industrial incineration facilities and various mobile sources. On the other hand, a large portion of OLE (Olefin) emissions are speciated from mobile sources in addition to those contributed by the polypropylene industry in point source. It was found that FORM (Formaldehyde) is mostly emitted from petroleum industry and heavy duty diesel vehicles. Chemical speciation of PM2.5 emissions shows that PEC (primary fine elemental carbon) and POA (primary fine organic aerosol) are the most abundant species from diesel and gasoline vehicles. To reduce uncertainties in processing the Korea emission inventory due to the mapping of Korean SCCs to those of U.S., it would be practical to develop and use domestic source profiles for the top 10 SCCs for area and point sources and top 5 SCCs for on-road mobile sources when VOC emissions from the sources are more than 90% of the total.

Verification experiment of a ground source multi-heat pump at cooling mode (지열원 시스템 히트펌프의 냉방 성능 특성에 관한 실증 연구)

  • Lim, Hyo-Jae;Kang, Shin-Hyung;Choi, Jae-Ho;Choi, Jong-Min;Moon, Je-Myung;Kwon, Young-Seok;Kwon, Hyung-Jin;Kim, Rock-Hee
    • Proceedings of the SAREK Conference
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    • 2008.11a
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    • pp.21-26
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    • 2008
  • Recently, small and medium-sized buildings have employed a multi-heat pump. The major benefits of the multi-heat pump over a conventional system are that it is easier system to maintain along with a diversification of facility use, and high comfortability. The performance of multi-heat pump systems can be enhanced by using geothermal energy instead of air source energy. This paper describes the multi-heat pumps applied in an ground source heat pump system for an actual building. The performance of a ground source multi-heat pump installed in the field was investigated in cooling mode. The maximum COP of the systems with single U-tube and double tube ground loop heat exchangers were 6.6 and 6.0, respectively. It is suggested that the new algorithms to control the flow rate of secondary fluid for ground loop heat exchanger have to be developed in order to enhance the performance of the system.

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A Proposal on the New Air Emission Source Categories (새로운 대기오염물질 배출원 분류체계에 관한 제언)

  • 홍지형;허정숙;이덕길;석광설;이대균;엄윤성
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.3
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    • pp.231-245
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    • 2002
  • A better knowledge of emission inventories can serve several important functions such as provision of public information, identification of primary sources, assessment of temporal and spatial trend, and analysis for national modelling studies. The purpose of this paper is to propose the new air emission source categories on the basis of the Korea Standard Industrial Classification. Hence, the paper focuses on reviewing and comparing the air emission sources categories of USEPA, and EU. The new emission source categories compose Tiers 1, 2, and 3. For Tier 1, there are 14 categories; fuel combustion-utilities, industries, and heating and others, chemical and allied product manufacturing, metals processing, and petroleum and related industries, etc. Tier 2 consists of small categories classified minutely in Tier 1. Tier 3 connects the categories of Tier 2 with the Korea Standard Industrial Classification.

The energy-saving effect by controlling the number of operating chillers in university facility (대학시설에 대한 열원기기 대수 운전 제어의 에너지 절약 효과)

  • Lee, Je-Hyeon;Akashi, Yasunori;Kum, Jong-Soo;Kim, Dong-Gyu
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.1043-1048
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    • 2009
  • This paper proposes the new operation control method that let heat source system stop and circulate only hot water at low load, and verified the introduction effect. At first, we constructed simulation model of heat source system and examined the proposing method by using simulation model. At last, we examined the introduction effect of proposing method with actual building. As a result, the primary energy consumption of heat source system was reduced by about 13%.

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Distribution between Air-Soil Concentration of Organochlorine Pesticides (유기염소계 살충제의 대기-토양간 분배)

  • Choi, Min-Kyu;Chun, Man-Young
    • Environmental Analysis Health and Toxicology
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    • v.22 no.4
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    • pp.299-304
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    • 2007
  • This paper was studied to investigate the equilibrium state between organochlorine pesticides (OCPs) concentration of air and soil, and to know whether soil is a secondary pollution source of OCPs in air or not. The OCPs concentration of air ($C_{air}$) and soil ($C_{soil}$) is not related to molecular weight, vapor pressure ($P_L$) and octanol-air partition coefficient ($K_{oa}$). The slope of the regression line between soil-air partition coefficient ($K_{sa}$) and scavenging coefficient ($C_{soil}/C_{air}$) was 0.2952, which the OCPs concentration between air and soil did not reached to the equilibrium state. The soil/air fugacity quotients ($f_{soil}/f_{air}$) of p, p'-DDT/DDD/DDE and ${\beta}-HCH\;(0.30{\sim}0.67$), which is smaller than 1, means the deposit of OCPs from air to soil. However, $f_{soil}/f_{air}$ of heptachlor, heptachlor epoxide, ${\alpha}/{\gamma}-chlordane$, trans-nonachlor, endosulfan sulfate and ${\alpha}/{\gamma}-HCH\;(1.90{\sim}73.25)$, which is greater than 1, means that soil is secondary pollution source of OCPs in air.

Case Study of Hybrid HVAC system Applied VRF (VRF 응용 Hybrid 공조시스템 Case Study)

  • Kim, Seong-Sil;Park, Wan-Kyu;Hur, Inn-Ju
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.357-362
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    • 2008
  • The present study has been conducted variable refrigerant flow system applied building. Multi air-conditioning system has some benefits : easier building management and maintenance and energy saving. Recently, the system heat pump has been employed in medium-sized and tall buildings. However, the performance data and design method for system heat pump are limited in literature due to complicated system parameters and operating conditions. In the present study, case study of a system heat pump applied various building. The aim of this paper is to application multi air-conditioners and to inform the benefits of multi air-conditioners.

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A Study on Estimation on Air Exchange Rate and Source Strength in Indoor Air Using Multiple Measurements of Nitrogen Dioxide (이산화질소 다중측정을 이용한 실내공기의 환기량 밀 발생량 추정에 관한 연구)

  • Yang, Won-Ho;Lee, Ki-Young;Chung, Moon-Ho;Zong, Moon-Shik
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.10 no.1
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    • pp.160-169
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    • 2000
  • Daily indoor and outdoor nitrogen dioxide ($NO_2$) concentration for 30 days were measured in 28 houses with questionnaire of housing characteristics in Brisbane, Australia. Using mass balance equation and regression analysis, penetration factors and source strength factors were calculated. The penetration factors of 27 houses except one house were between zero and 1, though penetration factor should be between zero and 1 by means of mass balance equation. Relationship between indoor and outdoor concentrations in each 27 house was calculated using regression analysis. According to the obtained linear regression equation, the slope means penetration factor and the intercept means source strength factor. Calculated mean and standard deviation of coefficients of determination ($R^2$) in electric and gas range houses were $0.70{\pm}0.13$ and $0.57{\pm}0.21$, respectively. The source strength factors were more than zero in 27 houses. Mean and standard deviation of slopes in electric and gas range houses were $0.65{\pm}0.18$ and $0.56{\pm}0.12$, respectively. Mean and standard deviation of intercepts in electric and gas range houses were $1.49{\pm}1.25$ and $5.77{\pm}3.55$, respectively. Air exchange rate and source strength were calculated from penetration factor and source strength factor, respectively. Geometric mean and standard deviation of calculated air exchange rates in 27 houses were $1.1/hr{\pm}1.5$. Presence of gas range was the most significant factor contributing to indoor $NO_2$ level in house characteristics (p=0.003). In gas range houses, source strengths ranged from 4.1 to $33.1cm^3/hr{\cdot}m^3$ with a mean $12.7cm^3/hr{\cdot}m^3$ and a standard deviation 9.8. The source strengths of gas range houses were significantly different from those of electric range houses by t-test (p<0.001)

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