Thermal Comfort in Outdoor Urban Space A Case Study in Konya City ...

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The city's specific microclimate determines the conditions of thermal comfort in ..... In these places, the canopy of the passage, designed with ivy type plants on ...
“kentsel dış mekanda Termal Konfor, Konya kent Merkezinde alan araştırması” Ekolojik Mimarlık ve Planlama Sempozyumu, International Ecological Architecture and Planning Symposium, 22-25 Ekim/October, Antalya, Mimarlar Odası Antalya Şubesi Yayınları, p. 89,94 English version

Thermal Comfort in Outdoor Urban Space A Case Study in Konya City Center Dr. Fatih Canan Abstract The human thermal comfort conditions in urban area are mainly affected by the microclimate. The thermal comfort sensation in outdoor spaces is a factor that significantly influences the human activities. Comfortable outdoor spaces can avoid social exclusion and isolation. The case study is carried out in a main street transformed into pedestrian zone in 2005 which has a very intensive utilization in city center of Konya. Outdoor thermal comfort condition for warm days (summer period) was studied in the determined part of this pedestrian street with the Comfa method. In this study area, 9 different points were determined for thermal comfort calculation. The obtained results, showed the importance of shadowing. There is sensation of discomfort during the day in this points which are not shadowing from buildings and trees. It has been determined that in outdoor urban environment, suitable thermal conditions can be provided with trees, building façades, and consciously designed architectural elements. Keywords: thermal comfort, outdoor urban space, microclimate 1. Introduction For a sustainable urban development, it is necessary to conceive urban open spaces according to the psychosocial and physicals needs of the people. Open spaces in urban environment which have an important potential of use, must allow the improvement of life quality and the enrichment of city dwellers social life. To make livable these spaces in the future, at first phase of design, it is important to study sensitively the thermal comfort parameters from among of the physical parameters. The thermal comfort condition is an essential factor which determines the life quality of the outdoor spaces like esthetics and functionality. The city’s specific microclimate determines the conditions of thermal comfort in urban environment. The urban microclimate which affects the thermal comfort of the people is determined by many physical parameters like urban morphology, the geometry of space, the cover materials priorities of the ground and of the buildings frontages, the trees, the vegetations and the water elements. In urban environment, these parameters ensure the climatic conditions in a specific place. Different from rural areas, they can stimulate important changes in urban environment, concerning especially insolation condition and wind speed. The microclimatic diversity of outdoor spaces and possible effects of this diversity on space usage must be understood at the beg inning of design phase [1]. Outdoor spaces which have bad thermal comfort conditions can be the cause of social isolation which could especially decrease life quality of downtown in summer period. The goal of this study is to determinate the thermal comfort level of a person using Comfa method [2] in a limited part of the Zafer pedestrian zone which localized in Konya city center, during different time of a summer day. The computation results were obtained for a typical summer day by taking account the location, the spatial priority, the density of use and the diversity of activity. With obtaining results, in a general context, it was tried to develop new suggestions for the organization of the pedestrian zone. 2. Methodology The thermal comfort analysis of the study area, determined in the center of Konya, are carried out with Comfa method. Comfa method consists to determine comfort sensation of a person located in outdoor space with mathematical results. The thermal comfort condition is determined with the interaction between physical parameters of the surrounding environment and human physiological parameters The result are defined by the exchanges between metabolic energy and the energy of the outdoor environment. Obtained Numerical results are used to determine the thermal comfort satisfaction or dissatisfaction of a person. Energy balance (EB) [3] or the energy budget (B) [4] of a person located in outdoor environment, can be calculated with the following simple equation [2]. B (Budget) or EB = M + Kabs + Labs – Conv – Evap - TRemitted M: The metabolic energy used to heat up the person Kabs: : Total solar radiation received by a person

Labs : The terrestrial radiation absorbed by a person Conv: The convective heat flow from a person to the open air Evap: The energy lost by evaporation TRemitted: Terrestrial radiation emitted by a person

The budget value (B), obtained by calculations determine the comfort level of a person located in outdoor environment. If the budget (B) is near zero, the person is thermally comfortable. If the budget (B) presents a large value, the person receives more energy than lost, so overheating could occur and the person would be uncomfortably warm. Otherwise, if the budget (B) is a negative value, the person would be in discomfort due to cold [4]. The table 1 shows comfort levels of a people according to different ranges of the budget values. Table 1 Level of comfort sensation according budget value 2

Budget Value ( W/ m ) B < -150 -150 < B