乾暑・蒸暑地域におけるヴァナキュラー建築の温熱環境的特徴の解明に関する研究 : 現代に引き継がれるパッシブデザインの原点について

• Material Type: 博士論文
• Title: 乾暑・蒸暑地域におけるヴァナキュラー建築の温熱環境的特徴の解明に関する研究 : 現代に引き継がれるパッシブデザインの原点について
• Author/Editor: 菅原, 圭子
• Author Heading: 菅原, 圭子
• Publication Date: 2021-03-24
• Publication Date (W3CDTF): 2021-03-24
• Alternative Title: Research on elucidation of thermal environmental characteristics of Vernacular Architecture in hot arid and tropical regions : The origin of passive design inherited in modern times
• Degree grantor/type: 法政大学 (Hosei University)
• Date Granted: 2021-03-24
• Date Granted (W3CDTF): 2021-03-24
• Dissertation Number: 乙第248号
• Degree Type: 博士(工学)
• Conferring No. (Dissertation): 乙第248号
• Text Language Code: jpn
• Subject Heading: 乾暑地域; 蒸暑地域; ヴァナキュラー建築; 温熱環境
• Target Audience: 一般
• Note (General): type:Thesis; Part 1: IntroductionIn recent years, various efforts to reduce carbon dioxide have been carried out in various countries and industries in line with global warming. The construction industry are working toward the basic energy plan approved by the national government in 2016, “Aiming to realize ZEB (Net Zero Energy building) on average for new buildings by 2030”. In order to realize such zero-energy architecture, it is essential to use passive methods. Therefore, this study focused on the passive method seen in Vernacular Architecture which coexists with the natural environment. Vernacular Architecture is closely related to the climate. Looking at the relationship between the Koppen climate classification and the form, construction method and building materials of Vernacular Architecture, mostly soil and rocks are used as the building materials in the regions where vegetation is difficult to grow due to low precipitation. Underground is also used as housing in some places. Since tall trees are abundantly available in the regions with heavy precipitation, wood and grass are used as building materials. The floor is raised from the ground to promote ventilation. Therefore, in this study, the thermal environmental characteristics were researched and verified to explore the mechanism of the passive method especially for heat, targeting “hot arid areas” and “hot humid areas”.; Part 2: Hot Arid Regions Chapter 1Compared to Tokyo, the dry heat areas have high temperature all through the year and very little precipitation. Therefore, the Vernacular Architecture found in this region has the following characteristics:１） Most buildings adopt masonry construction method that mainly uses dried bricks and some are built underground or in caves.→ Creates delay in the heat peak hours and reduces the temperature difference of the room throughout the day.２） For the typical building structures, outside is closed and inside the building is opened.→ Streets are narrow and under shade. Each house has a courtyard that allows the air to pass through the building.３） Water features and ponds are placed inside the house in many cases.→ Placing “Water” in the path of the wind encourages humidification cooling.There are some regions where wind catchers are used for passive ventilation for leading the outside air into the building. Wind catchers have different shapes and structures, which depends on the prevailing wind. In this research, two different types of wind catchers were researched: “one-side type” that has one air inlet and “multisided type”, that allows the air go through more than one air inlet/outlet.Part 2: Hot Arid Regions Chapter 2The multi-sided type wind catchers were researched in Iran. All the wind catchers were partitioned with walls but the partitioning method was not uniform. The size, plane shape and height of wind catchers varied as well. However, it was found that in houses and public facilities with courtyards, the wind passes from the wind catcher to all the way to the courtyard. The larger the buildings, the larger the wind catcher tended to be. There were examples of humidifying and cooling the air by placing a water feature directly under the wind catcher, or allowing the air to the basement to cool it down before releasing it in the room. To verify the wind catcher effect, the air flow and temperature distribution in the wind catcher and the building were calculated using CFD analysis.The target buildings of the analysis were a house with one-sided wind catcher in Pakistan, a house with multi-sided wind catcher in Iran and the water reservoir called AB-Anbar. The thermal environmental change inside the houses in 48 hours was calculated using a non-stationary analysis. As for the water reservoir, there is no detailed written description of the internal thermal environment, and it is only prediction on paper. In order to obtain the new knowledge, the water reservoir was added to the study other than houses.Part 2: Hot Arid Regions Chapter 3As the result of the analysis, it was found that the one-sided type wind catcher has a role to supply airflow into the room where there were only few openings to obtain airflow. The air change rate of the room through the wind catcher was about 1.2 [time/min] although there was no airflow from the window. The air is exhausted from the opening such as ducts and voids in the center of the building, and played a very large role in ventilation. The first floor where there is no wind catcher and only little sunlight comes in is a storage room. The temperature change is small throughout the day compared to other rooms. The fluctuation of the room temperature of the first floor with all the windows closed is about 8 [°C] while that of outside is about 15 [°C]. In this way, the locations of the wind catcher and the windows and the arrangement of the rooms are devised depending on the purpose of use for thermal comfort for occupants.In houses with a multi-sided wind catcher, there is a wind path between the wind catcher and the courtyard. The inflowing air through the basement to the courtyard, and to the first floor then flows out of the wind catcher. During the day, air flow from the wind catcher is as small as 1.82 [m^3/s], but it goes up to 4.35 [m^3/s] early morning when there is wind blows from southeast. That means the wind catchers are designed to obtain much more of cooler air. Looking at the temperature changes in the basement during the dry season, it fluctuates between about 22 and 27 [°C] while that of outside fluctuates between about 19 and 32 [°C]. The basement was found to be very comfortable throughout the day.Part 3: Tropical Regions Chapter 1 and 2In hot and humid areas, there are many solutions due to the high humidity and heavy precipitation.１） Most building materials are grass and wood which are abundantly available and the feature of the building structure is stilt housing.→ The floor is raised from the ground to secure the air flow. Humidified and cooled air goes into the room by passing wind under the floor.２） The roof is large, and air vents are located on the gable or bargeboard.→ Allows the hot air accumulated at the top of the roof goes out from the air vent on gable or bargeboard to promote air flow.３） Large roof and underfloor space→ Provides the shade to block the strong sunlight on the equator.There are many existing houses of the Batak people distributed in Sumatra Island, Indonesia. Particularly the Batak Toba people around Lake Toba still live in Vernacular Architecture that have steeply-pitched saddle back roofs. The houses of the Batak Toba was subject to the field research of the thermal environment.; Part 3: Tropical Regions Chapter 3The thermal environment of two houses were measured in August. Those two houses were similar in shape, but one house had air vents in the gable (=the open gable house) and the other house was sealed (=the closed gable house). A comparative study of ventilation effects of those two houses was conducted.It was found that the wind speeds under the floors of both houses were so low that no air was entering inside through the gaps of the floor. However, the air change rate through the gaps between the wall and the roof for both houses was about 0.4 [time/min], which tells that the ventilation effect of the living space of both houses are the same. The room temperature at FL+2,000 [mm] or above, the closed gable house is about 5 [°C] higher than the open gable house, which tells that the ventilation effect of the gable air vent is large.The effect of the shadow cast by saddle back roof was roughly estimated to be more than twice the area of that of a gable roof based on photographs and the examination of the shade using 3D model.The new facts which were not written in the literature were found in the field survey. The Batak Toba people continued to live in a good fusion of modern life and Vernacular Architecture. The material of the roofs have become metal with no insulation, surrounded by home appliances, and the floor was covered with vinyl sheets to block the air flow from under the floor. The room was well ventilated using the gable air vents during the day. That allows the hot air inside the house to exhaust so the occupants get thermal comfort during the night.; Part 4: Conclusions Differences From Past Research Chapter 1From the above investigation, new facts that were different from what was expected were found. Although there is a theory that the wind catcher could be a solar chimney, there is little possibility that the air convection occurs during the night time since the wind catcher itself is not capable of storing heat as so much. There is an explanation that the air from the wind catcher circulates inside the house without going out. However from the field investigation of multiple houses, it was found that the air circulates between the wind catcher and the duct or courtyard rather than circulating in the same room. Although there is an illustration that there is a hole at the top of the dome for air exhausts in the water reservoir, actually there is no hole at the top of the dome. The wind catcher of the water reservoir does not actively take in the air during the day but it takes in cold air in early morning and exhausts it through the other wind catcher.Part 4: Conclusions Development to Modern Architecture Chapter2There are several examples of applying the passive method found in Vernacular Architecture to contemporary architecture.As it is a mixture of modern air conditioning and passive methods inherited in generations since ancient time, there remains lots of issues in its control and costs. It is significant for owners and occupants of the buildings to change their consciousness considering more about energy saving and environmental friendliness on top of the costs.
• DOI: 10.15002/00024122; https://doi.org/10.15002/00024122
• Persistent ID (NDL): info:ndljp/pid/11692113; https://dl.ndl.go.jp/pid/11692113
• Collection: 障害者向け資料
• Collection (Materials For Handicapped People:1): テキストデータ
• Collection (particular): 国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文; https://dl.ndl.go.jp/collections/A00014
• Acquisition Basis: 博士論文（自動収集）
• Date Accepted (W3CDTF): 2021-07-05T22:24:43+09:00
• Date Created (W3CDTF): 2021-06-17
• Format (IMT): PDF; application/pdf
• Access Restrictions: 国立国会図書館内限定公開
• Service for the Digitized Contents Transmission Service: 図書館・個人送信対象外
• Availability of remote photoduplication service: 可
• Periodical Title (URI): https://doi.org/10.15002/00024122; http://hdl.handle.net/10114/00024122
• Data Provider (Database): 国立国会図書館 : 国立国会図書館デジタルコレクション; https://dl.ndl.go.jp