日本ヒートアイランド学会論文集 vol. 06〜vol. 10


日本ヒートアイランド学会論文集 Vol.10 (2015)


15A001 学術論文
Comparison of daytime air heating amount between city and surrounding areas

菅原 広史 Hirofumi Sugawara*1 相曽 豪夫 Hideo Aiso*1 小田 僚子 Ryoko Oda*2  清野 直子 Naoko Seino*3

*1 防衛大学校地球海洋学科 Earth and Ocean Sciences, National Defense Academy of Japan

*2 千葉工業大学生命環境科学科 Life and Environmental Sciences, Chiba Institute of Technology

*3 気象研究所予報研究部 Forecast Research Department, Meteorological Research Institute

Radiosonde measurements were taken in Tokyo and its surrounding rural area in summer and autumn 2011. Simultaneous launch of radiosondes at four site clarified distribution of air heating amount. In calm fine daytime, air heating in the cental part of Tokyo is 93 Wm-2 (50%) larger than that of rural area. The mixing layer height is also ca. 50% larger in the urban area. Heat budget analysis revealed that urban-rural difference of the heating amount was mainly caused by the difference of surface sensible heat flux.


15B001 技術報告
Estimation and sensitivity check of the anthropogenic heat in Nagoya city

保刈 和也 Kazuya Hokari*1,2 近藤 裕昭 Hiroaki Kondo*1 亀卦川 幸浩 Yukihiro Kikegawa*3  井原 智彦 Tomohiko Ihara*4

*1 産業技術総合研究所 National Institute of Advanced Industrial Science and Technology (AIST)

*2 応用技術株式会社 Applied Technology Co.,Ltd.  (現職)

*3 明星大学 Meisei University

*4 東京大学 The University of Tokyo

In this study, we estimated the monthly averaged daily variation of anthropogenic heat (AH) in Nagoya city, where the frequency of the extremely hot day with the daily maximum temperature exceeding 35℃ is the highest among the three largest cities in Japan. The hourly AH was estimated with a horizontal resolution of about 500 m. In addition, we investigated the effect of the AH on surface air temperature by numerical simulations using a hydrostatic mesoscale model. As a result, the estimated AH explained 83% of the total energy consumption in Nagoya city in 2008. The peak values of the AH in downtown and industrial area were beyond 100 W/m2. The impact of AH on the surface air temperature was greater at night, and it was found that AH slightly modified the wind flow and convergenece zone in the city.


15A002 学術論文
都市気象官署における長期気温上昇率の時刻別・気象条件別評価 −JRA-55データを利用した52年間の解析−
Evaluation of Long-term Temperature Trends at Urban Meteorological Stations in Japan with Respect to Time of the Day and Weather Conditions: Analysis Using the JRA-55 Data.

工藤佳奈子 Kanako Kudo*1  藤部文昭 Fumiaki Fujibe*2

*1筑波大学大学院生命環境科研究科 Graduate School of Life and Environmental Sciences, University of Tsukuba
(現所属;日本気象協会 Present affiliation: Japan Weather Association)
*2 気象庁気象研究所 Meteorological Research Institute, Japan Meteorological Agency
(現所属;首都大学東京 Present affiliation: Tokyo Metropolitan University)

Data at 106 surface observation stations of the Japan Meteorological Agency and the Japanese 55-year reanalysis (JRA-55) for 52 years (1961 to 2012) were analyzed in order to evaluate urban-induced temperature trends with attention to the dependence on time of the day and weather conditions. Stations were categorized into four groups according to the population of municipalities in which they are located. For the nighttime of fine and weak wind days, the departure of observed surface temperature from the reanalysis 850hPa temperature, δT, has a positive trend which tends to increase with population, with values of 0.02-0.05 °C/year for the group of cities with population over a million. On the other hand, δT trends are generally small in the daytime and on days without sunshine. These features agree with the climatology of urban heat islands, which are enhanced in the nighttime under a fine and calm condition, indicating the influence of urbanization on long-term temperature trends at cities in Japan. However, δT trends have seasonal differences with larger values in spring and summer in comparison to autumn and winter, irrespective of time of the day and city population. This fact implies the contribution of some other factors than urbanization on δT trends, although their attribution will require further research.


15A003 学術論文
Development of a Surface Wetting Passive Cooling Louver System with Hydrophilic and Water Absorbing Coating Film and an Evaluation of its Fundamental Performance by Outdoor Experiment

平山 由佳理 Yukari Hirayama*1 太田 勇 Isamu Ohta*1 梅干野 晁 Akira Hoyano*2 

*1 (株)ミサワホーム総合研究所 Misawa Homes Institute of Research and Development Co.,Ltd.

*2 放送大学 The Open University of Japan

A Passive cooling louver system (PC louver) coated with hydrophilic and water absorbing film is developed in order to form cool microclimate in outdoor and semi-outdoor spaces. The PC louver was designed to shade direct solar radiation, provide radiation cooling and cool airflow. The results from the PC louver's outdoor experiment show that when more than 1 kg/h of water evaporated per vertical surface area (m2) during the day, PC louver's surface temperature was kept approximately to the ambient wet bulb temperature throughout the day, and air temperature passing through the PC louver decreased by -3℃ at most when enough water was supplied to wet the whole PC louver's surface.


15A004 学術論文

Craing FARNHAM*1 Masaki NAKAO*1 Masatoshi NISHIOKA*1  Minako NABESHIMA*1 Takeo MIZUNO*2 

*1 Osaka City University, Dept. of Urban Engineering, Osaka, Japan

*2 H. Ikeuchi & Co., Ltd., Osaka, Japan

Water mist of average droplet diameter near 20μm can be used to create pedestrain “cool spots” or help improve cycle efficieny of outdoor air conditioner units. Pump waste heat, sunlight and other factors may cause the supply water temperature to become warm. The effect of water temperature over the range from 8℃ to 92℃ on mist mass flow rate, droplet diameter, mist evaporation rate and cooling effect were measured. The temperature of air in the mist cone was also measured. It was found that an increase of water temperature from 27℃ to 60℃ yields 7% lower spray mass flow, 5% smaller Sauter mean diameter, and 6% faster evaporation. Temperatures inside the mist cone dropped below ambient within 20-40cm of the nozzle even when 92℃ water is sprayed. Increasing temperature of mist spray supply water could have use to speed evaporation in tight spaces, as a heat sink, or as a legionella countermeasure.


15A005 学術論文
Evaluation method of cooling energy savings by the high reflectance paint based on field observation

竹林 英樹 Hideki Takebayashi*1 山田 智博 Chihiro Yamada*1 石井 悦子 Estuko Ishii*1  三木 勝夫 Kastuo Miki*2 

*1 神戸大学大学院工学研究科 Gradeate School of Engineering, Kobe University

*2 三木コーティング・デザイン事務所 Miki Coating Design Office

Cooling energy savings in a building with the roof coated by high reflectance paint are examined based on field observation. It is diffcult to recognize the energy savings by using the date observed every hour. It is assumed that factors affecting to cooling energy load are the internal heat generation, the set temperature, weather conditions, ect. From the analysis on the relationship between in-outdoor air temperature difference and electric power consumption for air conditioner, which are averaged and integrated into every day, the reduction of electric power consumption by high reflectance paint coating is estimated. Analysis methods of in-outdoor air temperature difference and internal heat generation are discussed for more accurate estimation of cooling energy savings.


15B002 技術報告
姫路市におけるヒートアイランド研究 ―気温分布の季節変化観測
Urban heat island observation in Himeji city: Seasonal variation of the horizontal and vertical temperature profile

古橋 和樹 Kazuki Furuhashi*1 河野 仁 Hitoshi Kono*2

*1 ㈱創発システム研究所 SOHATSU Systems Laboratory Inc.

*2 兵庫県立大学名誉教授 Professor Emeritus at University of Hyogo

To study the urban heat island, we observed temperature at six sites in the city of Himeji over 21 months. The temperature was compared with those observed by the Automated Meteorological Data Acquisition System in Himeji (urban area), Fukusaki (rural area) and Ieshima (island). The vertical temperature profile was simultaneously observed on a tower at 18-m and 70-m heights. The results show that under land breezes, the average urban-rural temperature difference in early morning was 1.7°C in January and 1.4°C in August. The average urban-seaside temperature difference under sea breezes was 0.7℃ at 12:00 in August. Temperature varied with downwind distance from the upwind edge of the Himeji urban area, under land or sea breezes. Potential temperature differences between the urban surface (18-m height), urban upper level (70-m height) and rural surface (1.5-m height) were small during January daytime. However, these differences were large during August daytime because of strong solar radiation.


15A006 学術論文
Influence of small green park to surrounding building area

竹林 英樹 Hideki Takebayashi*1 八木 里英子 Rieko Yagi*1

*1 神戸大学大学院工学研究科 Gradeate School of Engineering, Kobe University

To the question that how long are air temperature reduction effects in the surrounding urban area affected by a small green park, horizontal air temperature profile in the leeward area of small green park are examined based on measurements results carried out in Kobe city and the numerical model to represent the advection and diffusion effects. Measurements results conducted in Tokyo and Osaka are also compared with the calculation results. It is considered that air temperature is dominated in accordance with the heat budget conditions in the urban area in more than about 50m from the green park.


15A007 学術論文
Prediction of Cool Air Distribution with the Consideration of Wind Direction Change by Superimposing CFD Analysis Results
-Application to a Semi-enclosed Space Consisting of Evaporative Cooling Walls -

平山 由佳理 Yukari Hirayama*1 浅輪 貴史 Takashi Asawa*2 梅干野 晁 Akira Hoyano*3

*1 ㈱ミサワホーム総合研究所Misawa Homes Institute of Research and Development Co., Ltd.

*2 東京工業大学 Tokyo Institute of Technology

*3 放送大学 The Open University of Japan

This paper proposes a method for the prediction of cool air temperature distribution and the appearance frequency of cool air under breezy conditions, considering the changes in the wind direction. It is seen from the measurement results in a semi-enclosed space consisting of evaporative cooling walls, that the appearance frequency of cool air is an important factor in the prediction of air temperature distribution during a breeze. In order to predict the air temperature distribution of cool air, CFD simulation results of mean flows in 8 wind directions were superimposed, considering the appearance frequency of upper wind in these directions. The results of the prediction of cool air appearance frequency showed good agreement with the measurement results, and from the superimposed image, the characteristics of the air temperature distribution could be visualized well.


日本ヒートアイランド学会論文集 Vol.9 (2014)

14A001 学術論文
An Observational Study of the Difference on Urban Heat Islands between Summer and Winter in Osaka City

奥 勇一郎 Yuichiro Oku*1 桝元 慶子 Keiko Masumoto*1

*1 大阪市立環境科学研究所 Osaka City Institute of Public Health and Environmental Sciences

In order to clarify the spatial and temporal variation of surface air temperature patterns in Osaka City, we applied principal component analysis and cluster analysis to characterize its diurnal variation patterns using 10-minute interval surface air temperature data obtained at 60 stations both in summer (July to August 2011) and in winter (December 2012 to February 2013). The first principal component in summer (winter), which the authors interpreted as characteristic of night time air temperature, explained 51.9% (60.4%) of the total variance. The second one, which was interpreted as characteristic of daytime air temperature, explained 27.1% (26.2%) of that. We found central area in Osaka City experience higher temperatures at night than surrounding areas due to the urban heat island effect. For the cluster analysis, 60 stations were grouped into 4 (3) types of diurnal variation of surface air temperature patterns in summer (winter), which were described by daily minimum temperature which acts as a primary factor and, only in summer, daily maximum temperature which acts as a secondary factor.


14A002 学術論文
Analysis of Land Surface Temperature and Hot Environment by using the Thermal Image Data

伊東 大悟 Daigo Ito*1 森田 真一 Shinichi Morita*1 田中 勝哉 Katsuya Tanaka*1
後藤 圭二 Keiji Goto*2 清水 桐郎 Kirio Shimizu*2 三笹 晶子 Akiko MIsasa*2

*1 株式会社パスコ PASCO Corporation

*2 吹田市環境部 Department of Environment, Suita City(平成23年度当時)

The purpose of this study is to investigate the actual situation of land surface temperature and is to analyze the hot environment. This research clarified the distribution of land surface temperature in Suita City by using a thermal infrared sensor mounted on an aircraft. By using the thermal image data, the effects of land use on the temperature was revealed quantitatively. We developed the model to explain the Grove temperature and WBGT (Wet-Bulb Glove Temperature) which is the index of hot environment. This model figured out the effects of solar radiation and land surface temperature on WBGT.


14B001 技術報告
Surface Temperature Distribution in Sakai City Area Estimated from Aerial Observation of Infrared Thermal Images

安田 龍介 Ryusuke Yasuda*1 中川 文里 Fumisato Nakagawa*1 吉田 篤正 Atsumasa Yoshida*1

*1 大阪府立大学大学院工学研究科 Graduate School of Engineering, Osaka Prefecture University

We have estimated the distribution of the surface temperature in Sakai city, at 1400 LST and around 2300 LST in midsummer, from the infrared thermal image data obtained from aerial observations and the ground level measurements. The relation between land use and the surface temperature were investigated.
In the daytime the surface temperature of the area where latent heat transport is dominant (sea, river, forest, park, etc.) is relatively low, however, the surfaces of their surroundings are not cooled because the surface temperature largely depends on the thermal characteristics of the surface material. In the nighttime, the surface temperature of inland water, such as reservoir ponds and moats of ancient tombs, shows the highest value among the land use categories. In the daytime the surface temperature of the middle- and high-rise residential areas is almost same as the low-rise spaced residential area. On the other hand, the surface temperature of the middle- and high-rise residential areas shows relatively higher value than the low-rise spaced residential area in the night time because the heat capacity of the buildings is large and the covering ratio of paved surface is high.


日本ヒートアイランド学会論文集 Vol.9-2 (2014)
Special Issue "the 7th Japanese-German Meeting on Urban Climatology"はこちら


日本ヒートアイランド学会論文集 Vol.8 (2013)

13A001 学術論文
Thermal Environment Improvement by Using Kudzu (Pueraria lobata (Willd.) Ohwi)in Rooftop Gardening

多田 雄一 Yuichi Tada*1 田代 崇郎 Takao Tashiro*1 坪井 聡史 Satoshi Tsuboi*2

*1 東京工科大学・応用生物学部 Sch. of Biosci. Biotechnol., Tokyo Univ. of Technol.

*2 東京工科大学・院・バイオ情報メディア研究科 Grad. Sch. of Bionics Computer Media Sci., Tokyo Univ. of Technol.

In order to utilize kudzu for rooftop gardening, appropriate cultivation methods of Kudzu were examined. The temperature of the concrete surface covered with potted kudzu was 5℃ lower than that of a non-shaded surface, and the temperature with hip-hydroponics cultivated kudzu was 10℃ lower. This result indicates that improvement in the thermal environment provided by kudzu is affected by the cultivation method. Among three plants species tested, the conductance and evapotranspiration rate were highest for hydroponics cultivated sweet potato, followed by hip hydroponics cultivated kudzu and then potted kudzu, indicating that the improvement in the thermal environment of concrete surface temperatures provided by plants is affected by the amount of evapotranspiration. It was also suggested that kudzu plants in Japan are diversed in the conductance, evapotranspiration rate and photosynthesis rate, which are related to ability to improve thermal environment.


13A002 学術論文
初冬早朝における緑地内外の気温分布調査 -代々木公園・明治神宮の事例-
An Investigation of air temperature distribution in-and outside of a wooded area in early winter morning -A case study for the Yoyogi-park and the Meiji-shrine-

岡田 牧 Maki Okada*1  若月 泰孝 Yasutaka Wakazuki*2  犬飼 俊 Shun Inukai*1  廣田 陸 Riku Hirota*1  日下 博幸 Hiroyuki Kusaka*3

*1 筑波大学大学院生命環境科学研究科 Graduate School of Life and Environmental Sciences, University of Tsukuba

*2 筑波大学アイソトープ環境動態研究センター Center for Research in Isotopes and Environment Dynamics, University of Tsukuba

*3 筑波大学計算科学研究センター Center for Computational Sciences, University of Tsukuba

A field experiment was performed in and surrounding built-up areas of the wooded area consisting of Yoyogi-park and Meiji-shrine in Tokyo on 1 December 2012 to examine the cool-spot phenomenon in early winter. The air temperature difference between the park and the surrounding built-up area was 1.8~2.9°C. The height of stable boundary layer reached 25m above ground level in the park during calm conditions. Air temperatures increased consistantly from the center of the park toward to the park boundary, but air temperature differences between inside the park and the surrounding built-up areas differed by location. For example, the air temperature difference in the east side of the park was 2.3°C, but it was 1.8°C in the west side. The largest air temperature difference was 2.9°C around Shibuya-station. The spatial distribution of the heights of buildings around the park was inhomogeneous to north, south, east, and west. For example, the average number of building floors in the south side of the park was higher than the west side. There was a positive correlation between the average number of building floors and air temperature difference from each of the built-up areas around the park. These results indicate the difficulty of selecting location points for obtaining the average air temperature difference between the park interior and surroundings.


13A003 学術論文
Parameter adjustment and application to an extension area of Okada and Kusaka’s formula for the black globe temperature

岡田 牧 Maki Okada*1  岡田 益己 Masumi Okada*2  日下 博幸 Hiroyuki Kusaka*3

*1 筑波大学大学院生命環境科学研究科 Graduate School of Life and Environmental Sciences, University of Tsukuba

*2 岩手大学農学部 Faculty of Agriculture, Iwate University

*3 筑波大学計算科学研究センター Center for Computational Sciences, University of Tsukuba

Globe temperature is an important element of the Wet-bulb Globe Temperature (WBGT). The formula, derived in our previous study to estimate the globe temperature, was applied to the long-term records observed at four major cities; Tokyo, Nagoya, Osaka and Fukuoka. The ranges of the meteorological variables in the observation were large; solar radiation ranging from 2.8 W/m2 to 1083.3 W/m2 and wind speed ranging from 0.0m/s to 14.8m/s. The parameters of the equation were newly determined by fitting the equation to those records. The equation thus obtained as a function of solar radiation and wind speed estimated the observed globe temperature with root mean square error (RMSE) of 2.3 ℃. The errors in estimates by the equation changed largely neither city to city nor year to year. We thus, concluded that the equation with newly determined parameters was applicable to a wide range of climatic conditions and usable to predict WBGT.


日本ヒートアイランド学会論文集 Vol.7 (2012)

12A001 学術論文
Urban heat island phenomenon observed in open spaces in Tsukuba city on clear summer days: An evaluation of uncertainty in urban-rural temperature difference

日下 博幸 Hiroyuki Kusaka*1 髙根 雄也 Yuya Takane*2 阿部 紫織 Shiori Abe*2
高木 美彩 Midori Takaki*2,3 重田 祥範 Yoshinori Shigeta*4 大橋 唯太 Yukitaka Ohashi*5
布和 宝音 Buhe Baoyin*2,6

*1 筑波大学計算科学研究センター Center for Computational Sciences, University of Tsukuba

*2 筑波大学大学院生命環境科学研究科 Graduate School of Life and Environmental Sciences, University of Tsukuba

*3 横浜市 Yokohama City(現所属)

*4 立正大学地球環境科学部 Faculty of Geo-environmental Science, Rissho University

*5 岡山理科大学生物地球学部Faculty of Biosphere-Geosphere Science, Okayama University of Science

*6 千葉大学大学院理学研究科 Graduate School of Science, Chiba University(現所属)

A field experiment was performed in 25 parks and school yards in Tsukuba city, Ibaraki Prefecture, for 6-9 August 2008 to examine city-scale urban heat island phenomenon on clear summer nights. In addition, uncertainty in urban-rural temperature difference associated with observation site selection is evaluated. The results show that a center of heat island with the highest temperature is found in downtown Tsukuba near the Tsukuba station. Secondary centers are found around the Kenkyu-gakuen station, as well as in the boundary between Tsukuba and Tsuchiura cities. Nocturnal temperatures observed at four rural sites are similar to each other, but temperatures in four sites in the city center varied by >1℃ depending on time. The uncertainty range in temperature difference between particular sites inside and outside of urban area mau be as large as 2.2℃


12A002 学術論文
An observational study on the mitigating effect of thermal environment by vegetation in the Hikarigaoka Nerima, Tokyo

橘 泰大 Yasuhiro Tachibana*1  高橋 洋 Hiroshi G. Takahashi*1,2,3  清水 昭吾 Shogo Shimizu*3

*1首都大学東京 都市環境学部Faculty of Urban and Environmental Sciences, Tokyo Metropolitan University

*2海洋研究開発機構,地球環境変動領域Research Institute for Global Changes,Japan Agency for Marine-Earth Science and Technology

*3首都大学東京大学院 都市環境科学研究科Graduate School of Urban and Environmental Sciences,Tokyo Metropolitan University

This study demonstrated a mitigation effect of thermal environment by vegetation in the Hikarigaoka housing complex, Nerima, Tokyo, in summer, using our observed surface air temperature, humidity and Wet Bulb Globe Temperature (WBGT). It was found that surface air temperature of the inside of the housing complex was lower than that of the outside both in daytime and nighttime, which suggested temperature was reduced by evapotranspiration of the vegetation in daytime. On the other hand, higher relative humidity in the inside of the housing complex was observed, compared with that in the outside. Particularly, relative humidity in the inside of the housing complex reached nearly saturated condition in nighttime. This result may suggest tree-planting leads to not only reduction of high temperature but also high relative humidity as an adverse effect in nighttime.


12A003 学術論文
IPCC SRES A2シナリオ下での三大都市圏の夏季気候の将来予測: WRF-UCMによる力学的ダウンスケーリング
Urban climate projection in the 2070’s Augusts for the three major metropolitan areas under the IPCC SRES A2 emission scenario: Dynamical downscaling by the WRF-UCM

髙根 雄也 Yuya Takane*1 日下 博幸 Hiroyuki Kusaka*2 原 政之 Masayuki Hara*3

*1 筑波大学大学院生命環境科学研究科 Graduate School of Life and Environmental Sciences, University of Tsukuba

*2 筑波大学計算科学研究センター Center for Computational Sciences, University of Tsukuba

*3 独立行政法人海洋研究開発機構 地球環境変動領域 RIGC, Japan Agency for Marine-Earth Science and Technology

There are few studies that conducted urban climate projection using Regional Climate Model (RCM) with high horizontal resolution that is capable of resolving urban area. In this study, urban climate projection for the 2070’s August for the three major Japanese metropolitan areas was performed by the Weather Research and Forecasting (WRF) model with 3-km grid increment coupled with un Urban Canopy Model (UCM). Dynamical downscale approach is adopted to simulate 2070’s urban climate using MIROC3.2-medres with IPCC SRES A2 emission scenario as a downscale source. The observed characteristics of heat island at early morning is well simulated both in 2000s and 2070s on the three major metropolitan area. Surface air temperatures at 5 Japan Standard Time (JST) in 2070’s in Nerima (Tokyo), Nagoya, and Osaka are 27.5℃, 28.5℃, and 28.7℃, and are 3.1℃, 2.9℃, and 3.2℃ higher than that of 2000’s, respectively. As in observations, the simulated mid-day (14 JST) temperature is the highest in the inland areas of the three major cities both in 2000s and 2070s. The temperature at 14 JST in 2070’s in Nerima, Nagoya, and Osaka are 33.6℃, 34.9℃, and 34.9℃, and are 3.1℃, 3.4℃, and 3.0℃ higher than that of 2000’s, respectively.


12A004 学術論文

Craig FARNHAM*1 Akito TAKAKURA*2 Masaki NAKAO*1 Masatoshi NISHIOKA*1

*1 Osaka City University, Dept. of Urban Engineering

*2 Osaka City Institute of Public Health & Environmental Sciences

The City of Osaka has several urban waste-to-energy incineration facilities that both contribute to, and are affected by, the urban heat island. Applying mist evaporative cooling to the forced-draft, air-cooled condensers at these plants can both reduce the exhaust air temperature and increase the amount of electricity produced. The condenser reaches over 70℃ and the exhaust is released at 30m height. Power output drops by over 1%/℃ as air temperatures rise in summer. A misting system was installed over 1/8 of the air intake at a 14.5MW plant. Water droplets with a Sauter mean diameter of 45 microns were sprayed at up to 2.88tons/hr with near-complete mist evaporation. The exhaust air temperature dropped an average of 1.0K. If implemented full-scale, it should yield exhaust temperature reductions of 4-5K. The cooling effect increased the power output by 1.2% for misting periods greater than 45 minutes, but uncertainty is high. Full scale use at all Osaka plants during the summer could increase power generation by 6MW, offsetting 1700 tons of CO2 per season.


日本ヒートアイランド学会論文集 Vol.7-2 (2012)
[Special Issue "the Heat Island 2009 Conference"]はこちら


日本ヒートアイランド学会論文集 Vol.6 (2011)

11A001 学術論文
Field Experimental Results on the Rooftop Green with the Textile Mats - The Power Saving Effect of Air-Conditioner in Summer -

川島 久宜 Hisanobu Kawashima*1  加藤 千尋 Chihiro Kato*2  鑓田 祥啓 Yoshihiro Yarita*3
黒岡 秀次 Hidetsugu Kurooka*4  石間 経章 Tsuneaki Ishima*1

*1 群馬大学 Department of Mechanical System Engineering, Gunma University

*2 宇部日東化成 株式会社 Ube – Nitto Kasei Co., LTD (当時群馬大学・院)

*3 群馬大学・院 Department of Mechanical System Engineering, Gunma University

*4 日和サービス株式会社 Nichiwa service LTD.

The field experiment with the rooftop green was tested to confirm the energy serving on the air-conditioner.The two prefabrication rooms set on the housetop at the ATEC in Gunma University. The greening was constructed to the rooftop of one of the rooms, and another rooftop was no changed. The temperatures were measured with K type thermocouple at the inside of the mat, roof, ceiling, several points in the room, and floor. The electric power of the air-conditioner was also recorded. The roof temperature of the greening room became smaller than that of another one. By using roof green, the electric power of the air conditioner decreased 16% in a day against the non-greening room. Furthermore, the power saving effect through August was reached until 11%.


11A002 学術論文
Thermal radiant environment measurements with fractal blind

中村 美紀 Miki NAKAMURA*1 酒井 敏 Satoshi SAKAI*1 大西 将徳 Masanori ONISHI*2
古屋 姫美愛 Kimie FURUYA*3

*1 京都大学大学院 人間・環境学研究科 Graduate School of Human and Environmental Studies, Kyoto University

*2 日本科学未来館 The National Museum of Emerging Science and Innovation(Miraikan)

*3 京都大学 理学部 Faculty of Science, Kyoto University

It is scorching hot in urban area under the strong sunshine of the summer. It is because that the surface temperature of the urban area is higher than the rural and the thermal radiant environment is poor. This poor environment in urban area can be greatly improved by fractal sunshades. The sunshade consists of many units of Sierpinski’s tetrahedron which has the almost same fractal dimension as trees. This paper shows results of comparative measurements of radiant environment in visual, near-infrared and thermal infrared bands under the fractal sunshade and a parasol. The results showed that the MRT under the sunshade was lower by 17 degree than that under the parasol. Furthermore, some sensory tests and long term measurements showed some results favorable to the sunshade.


11A003 学術論文
Urban Heat Island at Typical Summer Nights in Kofu Basin

赤塚 慎 Shin AKATSUKA*1 宇野 忠 Tadashi UNO*1 十二村 佳樹 Yoshiki JUNIMURA*2 杉田 幹夫 Mikio SUGITA*1

*1 山梨県環境科学研究所 Yamanashi Institute of Environmental Sciences

*2 岐阜大学地域科学部 Faculty of Regional Studies, Gifu University

In this study, we tried to examine the actual condition of urban heat island at typical summer nights in Kofu basin by analyzing the nocturnal temperature at fixed observation points. In order to examine the spatial characterization of thermal environment, 38 observation points were divided into four groups, and respectively analyzed the number of hot summer nights day, temperature depression during nights, and mean temperature in each group. In addition, mean nocturnal temperature of each time was mapped by interpolating the data at fixed observation points. From these analyses, it was found that the hotter area remains until early morning and hot summer nights occur more frequently around the center of Kofu basin. On the other hand, in the west and east part of Kofu basin, the number of hot summer nights day is smaller and the range of temperature depression is higher. This is because the ratio of artificial land cover and the effects of rivers and terrain are different from each group.


11A004 学術論文
- 続報:冬期における暖房の消費エネルギの比較 -
Field Experimental Results on the Rooftop Green with the Textile Mats
- 2nd Report: The Comparison of the Electric Power on the Air-Conditioner in Winter -

川島 久宜 Hisanobu Kawashima*1 加藤 千尋 Chihiro Kato*2 鑓田 祥啓 Yoshihiro Yarita*3 黒岡 秀次 Hidetsugu Kurooka*4 石間 経章 Tsuneaki Ishima*1

*1 群馬大学 Department of Mechanical System Engineering, Gunma University

*2 宇部日東化成 株式会社 Ube ? Nitto Kasei Co., LTD (当時群馬大学・院)

*3 群馬大学・院 Department of Mechanical System Engineering, Gunma University

*4 日和サービス株式会社 Nichiwa service LTD.

A field experiment with a rooftop green on a prefab container was performed to compare with an electric power saving effect on an air-conditioner in winter season. The two prefabs were set on the housetop of the ATEC in Gunma University to compare the rooftop green effect to the building. In this experiment the temperatures at an atmosphere, rooftop, ceiling, and inside of the prefab were recorded with the thermocouple. The electric power of the air-conditioner was also recoded. The electric power on the prefab with the rooftop green became larger than that without rooftop green, because the textile mat for the rooftop green had been cooled while the nighttime. Then, large electric power was spent to increase of the room temperature.


11A005 学術論文
A Study of Pavement Body Configurations of the Evaporative Cooling Pavement System with a Focus on Rainwater Retention and Capillary Absorption through a Summer Outdoor Experiment

梅干野 晁 Akira Hoyano*1 円井 基史 Motofumi Marui*2 松本 明広 Akiriho Matsumoto*3 浅輪 貴史 Takashi Asawa*1

*1 東京工業大学大学院総合理工学研究科 Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology

*2 金沢工業大学環境・建築学部 College of Environmental Engineering and Architecture, Kanazawa Institute of Technology

*3 ㈱日建設計 Nikken Sekkei Ltd.

This paper discusses a pavement body configuration of the evaporative cooling pavement system. The evaporative cooling duration of pavement systems, which were designed with a focus on rainwater retention and capillary absorption, was investigated through a summer outdoor experiment. The results from this experiment showed the following: (1) Surface temperature of a system which has pavement blocks with arched void kept low for 14 days or longer. The difference between the surface temperature and air temperature were below 5 degrees C in the daytime. It is because the water retention capacity is enough and the distance of pavement surface and waterproof layer is shorter than the pavement capillary absorption height. (2) Evaporative cooling duration of pavement systems with a thick roadbed was about 5 days. It shows that there is stay water (not used for evaporative cooling) in the system after capillary absorption channel from the pavement downside to the surface are disrupted.