• Title/Summary/Keyword: underground temperature

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A study about caculating the heating load of the wall of underground space to be used undereground temperature (지중온도를 이용한 지하공간 벽체의 난방부하 계산에 관한 연구)

  • Jeong, Soo-Ill
    • Journal of the Korean Solar Energy Society
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    • v.28 no.1
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    • pp.19-24
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    • 2008
  • The energy crisis is culminating for the life of the fossil fuel in the future which is come to end at $30{\sim}40$ years. Moreover above 90% of the energy in our country depend on importing and the crisis is more seγious than it of other countries. So architects devote low energy house research and it means underground space research have become public opinion. But there is not an accurate and utility method calculating the heating load of underground space. In this study it is proposed that the heating load is calculated by setting adiabatic thichness of soil and predicting underground temperature. The prediction of the underground temperature is calculated by the latitude, the level, the distance from sea, the condition of earth surface.

A Study on Air Pollution and Thermal Factors in Underground Shopping Center of Pusan Area (부산시내 지하생활권의 공기오염도와 온열인자에 관한 조사연구)

  • Choi, Sung-Yong;Moon, Deog-Hwan;Lee, Jong-Tae;Song, In-Hyuk;Lee, Cha-Eun;Lee, Sung-Min
    • Journal of Preventive Medicine and Public Health
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    • v.27 no.3 s.47
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    • pp.505-516
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    • 1994
  • For the purpose of preparing the fundamental data on air pollution in underground shopping center and also contributing to the health improvement of residents, the authors measured the level of $SO_2,\;NO_2,\;TSP,\;CO,\;CO_2$ and also some related factors as air temperature, air movement, relative humidity and mean radiation temperature at inside and outside of underground shopping center in Pusan from January to February and from July to August 1994. The results were as follows : 1. The mean concentration of CO within the underground shopping center was $3.1{\pm}1.3ppm$ in winter and $2.1{\pm}0.9ppm$ in summer. There was a negative correlation (p<0.01) between inner CO concentration and temperature in summer and no correlation between inner CO concentration and outer CO concentration in underground shopping center 2. The mean concentration of COE within the underground shopping center was $876{\pm}353ppm$ in winter and $757{\pm}125ppm$ in summer. There was a negative correlation (p<0.01) between inner $CO_2$ concentration and air movement in summer and positive correlation (p<0.05) between inner $CO_2$ concentration and outer $CO_2$ concentration in underground shopping center. 3. The mean concentration of $SO_2$ within a underground shopping center was $0.036{\pm}0.019ppm$ in winter and $0.040{\pm}0.013ppm$ in summer. There was a positive correlation(p<0.01) between inner $SO_2$ concentration and temperature in summer and positive correlation between inner $SO_2$ concentration and outer $SO_2$ concentration in summer and winter in underground shopping center. 4. The mean concentration of $NO_2$ within a underground shopping center was $0.052{\pm}0.038ppm$ in winter and $0.042{\pm}0.016ppm$ in summer. There was a no correlation between inner $SO_2$ concentration and thermal factors in summer and winter and low correlation between inner $SO_2$ concentration and outer $SO_2$ concentration in underground shopping center 5. The mean concentration of TSP within a underground shopping center was $430{\pm}214{\mu}g/m^3$ in winter, $366{\pm}73{\mu}g/m^3$ in summer, and very in excess of the atmospheric environmental quality standards of Korea ($150{\mu}g/m3{\downarrow}$). There was low correlation between inner TSP concentration and temperature in summer and high correlation between inner TSP concentration and outer TSP concentration in underground shopping center.

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A Study on the Yearly Thermal Environmental Characteristics in Underground Space (지하거주공간의 연간 열환경에 관한 연구)

  • Jeong, H.M.;Chung, H.S.
    • Journal of Power System Engineering
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    • v.2 no.3
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    • pp.27-33
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    • 1998
  • The room temperature and air conditioning load in the underground space have been investigated numerically by the unsteady heat conduction equation. The model room has 3 m in height and 10 m in width, and it's position in the underground depth are 0.5 m to 5 m. When the room was located around surface, the room temperatures were strongly influenced by the atmosphere. But the underground depth is more than 2 m, the yearly temperature amplitude was small and the temperature phase was delayed. Up to 5 m of the depth, the cooling and heating load was decreased rapidly, but over 10 m of the depth, the air conditioning load was constant.

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CHARACTERISTICS OF SMOKE CONCENTRATION PROFILES WITH UNDERGROUND UTILITY TUNNEL FIRE

  • Kim Hong Sik;Hwang In Ju;Kim Youn-Jea
    • Journal of computational fluids engineering
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    • v.10 no.1
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    • pp.94-98
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    • 2005
  • Accurate prediction of the fire-induced air velocity, temperature and smoke flow in underground utility tunnel becomes more important for the optimization of design and placement of heat and smoke detectors. In order to improve the safety of underground utility tunnel systems, the behaviors of fire-induced smoke flow and temperature distributions are investigated. Especially, two different cross-sectional shapes of tunnel, such as rectangular and circular types are modeled. Also, fire source is modeled as a volumetric heat source. Three-dimensional thermal-flow characteristics in an underground tunnel are solved by means of FVM using SIMPLE algorithm. The effects of shape geometry on the fire-induced flow characteristics are graphically depicted. It is desirable that heat and smoke detectors are installed on the cables and the top of the wall.

Establishment of Design Standard and Analysis of Insulation Property for Underground Space in Architecture (건축물의 지하공간을 위한 단열재의 특성 분석 및 설계 기준 수립)

  • Hwang, Min-Kyu;Cho, Woo-Jin;Kim, Kang-Soo
    • KIEAE Journal
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    • v.13 no.2
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    • pp.107-112
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    • 2013
  • The purpose of this study is to analyze an insulation property and to establish a design standard for the underground space in architecture. Insulation materials for this study are 12 kinds of Insulation which qualified KS standards(3 classes of EPS type 1, 3 classes of EPS type 2(Neopor), 3 classes of XPS and 3 classes of PU Boards). For insulation materials of underground space, insulating and water tightening property are desired. So conductivity for insulating and water absorption for water tightening are measured in this study. Temperature, insulation is exposed to in the underground space, is different from temperature above the ground. Conductivity is measured in a temperature of $17^{\circ}C$, $20^{\circ}C$, $23^{\circ}C$ and $26^{\circ}C$. In KS standards, water absorption are measure after 24 hours, but insulation is exposed to water for a long time in the underground. So after 110 days, water absorption are measured. As time goes by, increasing of water absorption means decreasing of water tightening and insulating. So after water absorption had measured for 110 days, conductivity has measured again. As a result, XPS is selected as optimized insulation for underground. And Conductivity of XPS insulation with water should be added by 20%.

Waterproofing Materials According to the External Environment of Non-exposed Waterproofing Materials for Underground Structures Performance Change Requirement (지하 구조물용 비노출형 방수재의 외부환경에 따른 방수재의 성능 변화 요구)

  • Jung, Suk-Joo;Song, Je-Young;Won, Seong-Jae;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.85-86
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    • 2020
  • In securing durability of underground structure non-exposed waterproof materials, the company aims to improve durability of waterproof materials by studying more realistic weather conditions than KS standards and developers' durability standards. Analyzing the actual climate data in Korea and the temperature of the basement layer, it is a waterproofing sheet method, a self-adhesive sheet method in which a film and a compound, which are currently widely used as underground water-proofing, and a self-adhesive waterproofing sheet method, etc. We would like to present the guidelines necessary to prevent the temperature situation and waterproof defects that are ideal for setting the endurance conditions later.

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Study on Air Washer using Underground Water in the Subway Stations (지하철 역사 지하수를 이용한 에어와셔에 관한 연구)

  • Kim, Dong-Gyu;Kim, Hoe-Youl;Chung, Yong-Hyun;Kim, Jong-Ryul;Kum, Jong-Soo
    • Journal of Fisheries and Marine Sciences Education
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    • v.22 no.4
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    • pp.604-610
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    • 2010
  • Busan subway transportation system has been established a key role in the society last 20 years. However many people are suffering from hot and humid environment at subway station and platform due to deteriorated ventilation system as well as insufficient air conditioning system in existing stations and platforms. As a result, these systems require revitalization. There is about 5400tons of low temperature underground water is generated from subway stations every day. By using this method and air washer we are trying to lower the temperature. Air washer is commonly used for removing humidity but in this experiment it will be used as air precooling. This research offers result of experiment using air washer system to lower the temperature in large spaces like subway station. The experiment result has shown when L/G was the same, at condition which water spray temperature at $18^{\circ}C$ resulting inlet and outlet temperature difference larger. Also, in the same water spray temperature conditions, larger L/G condition showed a greater temperature difference. LCC evaluation of both system were shown that air washer system of using underground water will save 53% of the initial cost than refrigeration system, and save 75% of operating cost.

Underground Heat Transfer Characteristics of the Underground Heating System for Soil Sterilization in Greenhouse (온실 내 토양소독을 위한 지중난방시스템의 지중 열전달 특성)

  • Park, Kyung-Kyoo;Ha, Yu-Shin;Hong, Dong-Hyuck;Jang, Seung-Ho;Kim, Jin-Hyun
    • Journal of Biosystems Engineering
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    • v.35 no.2
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    • pp.108-115
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    • 2010
  • This study was conducted to estimate the optimum temperature and required time for soil sterilization when heated water was circulated through underground heating pipes in the greenhouse which solar heat was influenced to the temperature of soil during the summer day. Two different types of heating pipes were used for the experiment. One was a polyethylene pipe(XL) and the other was a corrugated ring shaped stainless steel pipe(STS). The results of the studies were summarized as follows; By measuring the thermal characteristics of the XL and STS, it was examined that the average temperature differences of the inlet and outlet were $8.5^{\circ}C$ and $13.3^{\circ}C$, the average flowrates were 15.3 L/min and 5.6 L/min, and the average radiation powers were 9.1 kW and 4.1 kW, respectively. As results of the regression analysis of underground temperatures, when average soil temperature was$35^{\circ}C$, an average water temperature was $80^{\circ}C$, and XL was used, it was estimated that the possible heat transfer distance, the required time for heat transfer and heat flux to reach the underground temperature of $60^{\circ}C$ were 300 mm, 230 hours, and $7.57kW/m^2$, respectively.

Fluctuation Features and Numerical Model for Underground Temperature in Shallow Subsurface Soil (천층 토양 내 지중온도 변동 특성과 수치모델 평가)

  • Jeong, Jaehoon;Kim, Gyoobum;Park, Hyoungki;Kim, Hyoungsoo;Kim, Taehyung
    • Journal of the Korean GEO-environmental Society
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    • v.16 no.5
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    • pp.35-42
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    • 2015
  • This is conducted to observe underground temperature and to analyze its change affected by climate condition and soil infiltration in the mountainous area, Yesan region, Chungcheong-namdo province. Additionally, underground temperature change is also simulated using air temperature and soil thermal properties with a numerical model. Soil temperature monitoring data acquired from each depth, 20 cm, 50 cm, and 100 cm, indicates that the data within 50 cm in depth shows peak-shaped big fluctuation directly affected by air temperature and it at 100 cm has open-shaped small fluctuation. Underground temperature variation, a difference between high and low values, during monitoring period is weakly proportional to hydraulic conductivity of the sediment and it is assumed that water plays a part in delivering air temperature in soil. The underground temperature estimated by a numerical model is very similar to the observed data with an average value of 0.99 cross-correlation coefficient. From the result of this study, the aquifer unsaturated hydraulic conductivity of the soil and the groundwater recharge is likely to be able to estimate with underground temperature profile calculated using a numerical model.

A Study on the Adoption of optimum Construction Method to prevent Condensation on the wall of Underground Parking Lot in Apartment Project (공동주택 지하주차장의 벽체(壁體) 표면결로방지(表面結露防止)를 위한 적정 공법 선정에 관한 연구)

  • Oh, Kil-Hwan;Lee, Il-Jae;Kim, Sung-Gyu
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2007.11a
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    • pp.101-104
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    • 2007
  • Currently most of underground structures in domestic apartment projects are being designed for parking lot and essential parking area is growing due to the increase in car-holding number per household. Moreover, most underground parking lots of today are combined with basement, therefore a pleasant environment in underground space is strongly needed for the dwellers' use. However, there always occur high percentage of humidity and surface condensation in underground parking lot because of the nature of underground structure and they are having a bad influence on the comfort and health of dwellers. Therfore, this study is planned to compare and examine the porformance and properties of currently used construction methods to prevent condensation and finally present the most suitable method.

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