• 제목/요약/키워드: Globe temperature

검색결과 119건 처리시간 0.028초

하계에 도심지에서 관측된 흑구온도의 특성 분석 (On the Characteristics of Globe Temperature Variation Observed at Downtown in Summer Season)

  • 박종길;정우식;김석철;박길운
    • 한국환경과학회지
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    • 제17권8호
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    • pp.907-918
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    • 2008
  • In order to monitor the impact of high temperature which is seen frequently with climate change, we investigated the monthly change in globe temperature, air temperature, mean radiant temperature and effective radiant heat flow, because the four well reflect thermal radiation from bio-meteorological aspect. Both globe temperature and air temperature showed an increasing trend every month. Compared to air temperature, globe temperature had a wider range of temperature change and was more influenced by meteorological element such as precipitation. Diurnal trends of air temperature, globe temperature and the difference between their temperature had the lowest value before the sunrise and the highest around $1300{\sim}1500$ LST, showing the typical diurnal trends. Globe temperature and the difference between their temperature had a sharp increase around $1000{\sim}1100$ LST, maintained high value until 1700 LST and then reclined, though varied by month. The difference between globe temperature and air temperature was highly dependent on the amount of precipitation and clouds. The duration in which globe temperature was higher than air temperature was the lowest in July. Therefore the amount of precipitation was the most affecting, followed by the amount of clouds and wind. In order to find out the diurnal trends of temperature in city center and city outskirts, we assumed the roof of a concrete build ing as a city center, and the grass-covered observatory of the Gimhae International Airport as city outskirts. The diurnal trends of temperature in the two sites showed a strong correlation. The highest and lowest temperature also had the same trend.

하절기 도심과 외곽지의 열특성 비교 관측 (Study on Field Observations of the Thermal Environment in the Downtown Location and the Outskirt Site)

  • 정임수;최동호;이부용
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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    • pp.21-25
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    • 2009
  • This study is about heat island as one of the urban climate variation factors in urbanized modern society, which compared and observed the thermal characteristics both the downtown location and the outskirt site in summer. The diurnal air temperature range at each point is $12.6^{\circ}C$ in the downtown location and $14.3^{\circ}C$ in the outskirt site, so, it was found that the diurnal air temperature range in the outskirt site was $1.7^{\circ}C$ higher than in the downtown location. There was 20 minutes difference to reach the highest temperature between globe temperature and air temperature in the downtown location, however, the time spent to reach the highest temperature between globe temperature and air temperature in the outskirt site was the same. When we compared the globe temperature between the downtown location and outskirt site, we found that the temperature in the outskirt site was lower than in the downtown location after sunset due to the sudden temperature drops, although the exposed time to insolation in the outskirt site is longer. The average of globe temperature difference on the sample days was $1.1^{\circ}C$, the average of surface temperature difference on the sample days was $1.0^{\circ}C$, and the average of air temperature difference on the sample days was $2.0^{\circ}C$ Thus, it was found that the average of air temperature difference was higher than the average of globe temperature and the average of surface temperature. The result of this study is that the urban environment factors have more effect on the air temperature difference than globe temperature and surface temperature.

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LNG선박용 글로브 밸브 구조해석에 관한 연구 (A Study on Structural Analysis of Globe Valve for LNG Carrier)

  • 김동균;김정환
    • Journal of Advanced Marine Engineering and Technology
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    • 제31권8호
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    • pp.1013-1019
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    • 2007
  • This paper is about structural analysis of globe valve for controlling cryogenic LNG's flow or stop in normal temperature. The used valve is demanded safety resistance for inner pressure and temperature variation caused by using it in cryogenic, high pressure surrounding. This study evaluates for safety resistance for inner pressure and temperature variation by heat transfer analysis in cryogenic surrounding, heat stress analysis in temperature variation and deformation analysis in high pressure.

도심 녹음수의 체감온도지수(WBGT) 조절효과 (The Effect of Urban Shade Trees on the WBGT(Wet Bulb Globe Thermometer Index))

  • 주민진;이춘석;류남형
    • 한국조경학회지
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    • 제32권3호
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    • pp.51-59
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    • 2004
  • Focusing on WBGT(Wet Bulb Globe Thermometer Index) according to the LAI(Leaf Area Index) variation of trees, this study verifies the effects of urban shade trees on the outdoor thermal environment. As for methodology, air$.$globe temperature, air humidity and WBGT were measured under three shade trees whose LAIs were 2.1, 4.0 and 8.2 respectively at midday(12:00-13:00) of 14 sunny days from the 4th through the 29th day of September 2003. Those factors were also measured at the unshaded areas and compared with the values of shaded areas. The measured site was paved with interlocking concrete bricks. The measurements were analyzed through the ANCOV A(Analysis of Covariance) and the regression routines of SPSS11 for windows (SPSS Inc., 2001). The major findings were as follows. 1. The direct correlation between WBGT and LAI was very low. On the contrary, the WBGT showed close correlation with air$.$globe temperature and air humidity, and the LAI also showed very close correlation with globe temperature. These results tell that dominant shading effect by the tree is on the screening of direct solar radiation which lower the globe temperature and WBGT consequently. 2. While the average globe temperatures and WBGT at unshadowed area were 40.4$^{\circ}C$ and 26.2$^{\circ}C$ respectively, the former under the shade tree with LAI 2.1, 4.0 and 8.2 were 34.5$^{\circ}C$, 32.6$^{\circ}C$ and 30.2$^{\circ}C$, and the latter were 24.6$^{\circ}C$, 24$^{\circ}C$ and 23.4$^{\circ}C$ respectively. 3. The relationship between LAI(x) and WBGT(y) can be presented with the following equation: y = 24.23+1.53 $e^{-x}$+0.36x $e^{-x}$+0.46 $x^2$ $e^{-x}$ ($R^2$ =.98) =.98)

미기상 관측을 통한 하절기 도심과 외곽의 열환경 비교 (Comparison of the Thermal Environment in the Downtown Location and the Outskirt Site base on the Field Observations in the Summer)

  • 정임수;최동호;이부용
    • 한국태양에너지학회 논문집
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    • 제29권6호
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    • pp.94-101
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    • 2009
  • This study which is the fundamental work to investigate the property of urban climate compared the property of thermal environment in the downtown location and the outskirt site based on the field observation in the summer. We analysed thermal environment in the downtown location mainly by distributional characteristics during day and night with changes and correlation analysis of the air temperature, the globe temperature and the surface temperature through the simultaneous observation of the property of thermal environment at two places in real time. The summary of finding in this study is as follows. (1)It is observed on the day chosen by sample that diurnal air temperature range in the downtown location is $22.3{\sim}34.9^{\circ}C$, and diurnal air temperature range in the Outskirt site is $20.0{\sim}34.3^{\circ}C$, so, we found that the diurnal air temperature range in the outskirt site is $1.7^{\circ}C$ higher than in the downtown location. (2)In comparison of the globe temperature after sunset, we found the change of more sudden temperature drops in the outskirt site than in the downtown location. (3)It is observed on the days chosen by sample that the average of globe temperature range is $1.1^{\circ}C$, the average of surface temperature range is $1.0^{\circ}C$, and air temperature range is $2.0^{\circ}C$, thus, the we found that the average of air temperature is $1.0^{\circ}C$ higher than globe temperature and the surface temperature. (4)After the consideration of air temperature and globe temperature distribution, the highest temperature reaching time of globe temperature is one hour earlier than air temperature in the downtown location, on the other hand, although the highest temperature reaching time of globe temperature in the outskirt sites is one hour later than in the downtown location, the timelag found in the downtown location was not found in the outskirt site.

하절기 관측을 통한 도시의 지역별 공간녹지분포율에 따른 열환경 특성 연구 (Observational Study of Thermal Characteristics by Distribution Ratio of Green Area at Urban in Summer Season)

  • 정임수;최동호;이부용
    • 한국태양에너지학회 논문집
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    • 제31권3호
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    • pp.8-16
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    • 2011
  • The objective of this study is to analyze the characteristic of thermal environment in the summer season by conducting the field observation of temperature, relative humidity, and globe temperature in some parts of the city. Observation point was divided to a densely populated area, a residential area, a green area, a waterfront green area and a suburban district by the distribution ratio of green area. In this study, the correlation between maximum temperature and globe temperature, study on index for intensity of the tropical night and the temperature distribution characteristic of measurement points by the distribution ratio of green area were analyzed. The results of this study are as follows. (1) The difference between temperature and globe temperature by the distribution ratio of green area is confirmed. The difference of nighttime is more clearly that of daytime. (2) The average temperature and globe temperature of the densely populated area($29.2^{\circ}C$, $33.7^{\circ}C$) are higher than that of the waterfront green area($27.9^{\circ}C$, $32.0^{\circ}C$) by $1.3^{\circ}C$ and $1.7^{\circ}C$, respectively. (3) The number of tropical nights has different days of tropical nights by the distribution ratio of green area of 17days for the Daegu weather station, 14days for adensely populated area, 14days for a residential area, 6days for a green area, 2days for a waterfront green area, and 2days for a suburban district. (4) The results of the slope of trend line for the effects of the temperature on globe temperature change and the intercept for the size of the impact of radiant energy gained around by the analysis of the correlation between the maximum temperature and globe temperature can be utilized objective evaluation index of the each point's artificial effects.

아파트의 전면발코니 개조여부에 따른 겨울철 실내환경 측정비교 (Indoor Environmental Condition by Existing Front Balcony in Apartment House during Winter)

  • 최윤정
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2005년도 춘계학술발표대회 논문집
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    • pp.267-270
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    • 2005
  • The purpose of this study was to make clear the indoor environmental efficiency of front balcony 'in apartment houses during winter. The field measurements of indoor environmental elements were carried out at an ordinary house with an existing front balcony and a house renovated the front balcony into the living room. The measurements in two-subject houses were taken on simultaneously the 20$^{th}$ ${\sim}$ 21$^{th}$ of January 2003. As results, the averages indoor temperature in the ordinary house and the renovated house were same as 23.6${\circ}$C, and the averages globe temperature in two houses were same as 23.7${\circ}$C. But, estimated heating time of the renovated house was longer than that of the ordinary house. The daily ranges of indoor temperature and globe temperature in the renovated house were wider than the ordinary house. The daily ranges of indoor temperature and globe temperature in the renovated house was longer than that of the ordinary house. The uniformity ratio range of daylight in the ordinary house were calculated at 1/3.4${\sim}$1/6.2, but those of the renovated house were 1/6${\sim}$1/16.2. Therefore. it was found that indoor temperature, globe temperature and uniformity ratio of daylight in the ordinary house maintained more constant than the renovated house by green house effect and earning effect of front balcony.

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유한요소법을 이용한 극저온 미니어쳐 글로브 밸브의 구조설계에 관한 연구 (A Study on Structural Design of Cryogenic Miniature Globe Valve using Finite Element Method)

  • 정호승;조종래;김정환;김정렬;박재현;김영환
    • Journal of Advanced Marine Engineering and Technology
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    • 제31권4호
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    • pp.343-349
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    • 2007
  • This cryogenic miniature globe valve is used to transfer the liquified natural gas which temperature is $-169^{\circ}C$, supplied pressure is 30bar(3.0MPa). In the present work the temperature distribution and thermal deformation is calculated numerical the FE method is useful to predict the thermal matter of cryogenic miniature globe valve. For this reason, to optimum design of the cryogenic miniature globe valve the analysis of the parameter about bonnet has been studied. It's used 3-D modeling to analyze cryogenic globe valve, which is 1/2". Numerical study used 3-D modeling makes a decision of efficient process of product before producing in the factory. A commercial software(ANSYS 10.0) is used in the structural analysis for cryogenic globe valve.

수출 접목선인장 산취 '희망'의 주.야 온도 및 LED광 처리가 모구 생육과 발색에 미치는 영향 (Effect of Globe Growth and Chromogenic on Day and Night Temperature and the LED Light Treatment of Expert Grafted Cactus (Chamecereus silvestrii f. variegata) Cultivar 'Hee-Mang')

  • 남상용;박선미;안동현
    • 생물환경조절학회지
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    • 제19권3호
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    • pp.140-146
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    • 2010
  • 본 연구는 4개의 생육상에서 주간온도 $20^{\circ}C$$25^{\circ}C$, 야간온도 5, 10, 15, $20^{\circ}C$의 주 야 온도 조합과 적색LED, 청색LED, 분홍LED(청색LED+적색LED), 백색LED 4종의 발광다이오드(LEDs)를 조사하여 산취(Chamecereus silvestrii f. variegata)선인장 '희망'의 모구 생육 및 발색에 가장 효과적인 재배환경을 찾고자 실시하였다. 주 야 온도처리가 황색 모구의 고유색 발현에 미치는 영향은 명도($L^*$값), 적색도($a^*$값), 황색도($b^*$값)가 모두 유의성이 있으며 특히 주간온도 $20^{\circ}C$와 야간온도 $20^{\circ}C$에서 모구색이 선명한 황색으로 관상가치가 가장 높았고, 주간온도 $25^{\circ}C$$5^{\circ}C$, $10^{\circ}C$ 각각의 야간온도에서 모구색 품질이 저하되는 것으로 나타났다. 발광다이오드(LEDs) 처리는 $a^*$값과 $b^*$값에서 유의적 차이가 있으며 적색LED에서 $a^*$값은 +5.23, $b^*$값은 +39.9로 산취선인장의 고유의 아름다운 황색 발색을 유지하며 구색품질이 가장 좋았다. 따라서 산취선인장의 모구색 발현에 영향을 주는 최적 온도범위와 발광다이오드(LEDs)는 주간온도 $20^{\circ}C$와 야간온도 $20^{\circ}C$이며 단색광인 적색 LED에서 가장 효과적이었다. 또한 산취선인장 재배에서 모구색의 외적 품질 향상은 적정 온도 환경 유지보다는 광질 환경을 개선하는 것이 보다 효율적이며 특히 발광다이오드(LEDs) 적색LED가 황색계통의 고유한 모구색 발현에 효과적인 것으로 나타났다.

바닥난방 복사열에 의한 온열감 차이에 대한 실험연구 (An Experimental Study on Difference of Thermal Sensation by Radiant Floor Heating)

  • 최윤정;심현숙;정연홍
    • KIEAE Journal
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    • 제7권5호
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    • pp.65-71
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    • 2007
  • The purpose of this study was to analyze the difference of thermal sensation by radiant floor heating as ecological design element. The experimental investigations were carried out in climate chamber, and subjects were 34 college-age females in good health. The experimental variable was radiant heat by floor heating, and experimental controlled conditions were indoor temperature, relative humidity, and air velocity in climate chamber and clothing value and activity of subjects. The results are as follows. (1) Indoor temperature($21{\pm}0.5^{\circ}C$) in climate chamber were maintained as controlling. Clothing values of the subjects were controlled as average 0.73 clo. In the floor heating-off, globe temperature was average $23.2^{\circ}C$(22.4~24.1), but in the floor heating-on, globe temperature was average $24.8^{\circ}C$(23.0~25.5). (2) In the floor heating-off, thermal sensation rating was average -1.03(slightly cool), in the floor heating-on, thermal sensation rating was average +1.03(slightly warm). (3) There were the differences of thermal sensation by radiant floor heating although indoor temperatures were maintained in an equal state. (4) The thermal sensation rating was tending upward according as the globe temperature was getting higher.