مسکن و محیط روستا (Jun 2016)
An Analysis on the Orientation, Position and Dimensions of Wind-catchers in Vernacular Houses of Yazd
Abstract
Wind catchers in Yazd's traditional houses are the means to obtain optimal indoor climate against the heat in central plateau of Iran. It plays an effective role in modifying the temperature in the interior living spaces with regards to human thermal comfort. Wind-catchers are canals with the height of 3 meters mounted vertically on top of the roofs, resembling a chimney vent. The outlet openings in the upper end plays an effective role in modifying the heat and adjusting and regulating the temperature of the living space as appropriate for residents' comfort through convective wind flow using pure natural energy of nature. Relationship of the wind-catcher with the chamber and central yard has significant effect in its function. A chamber or a summer living quarter is directly and closely connected with a wind catcher. But in some instances this link is provided through the medium of an alternative space. In this research, a study of 24 houses in Yazd was conducted with an emphasis on the location and design of the wind-catchers. These houses were selected among Yazd's houses that have central yard and confirmed historical value. The data was collected through fieldwork. The data was subsequently analyzed through logical Inference and classification in excel software. In this research the classification system was based on 3 factors: 1. orientation of wind catchers; 2. their position in the house and the connection with the summer living quarters; 3. Design of the wind-catcher for optimum reception of the dominant winds. The canal of a wind catcher is usually divided into smaller sections by means of splitting blades. These blades rise 1.5-2 meters above the ground floor of the building and continue all the way up to the wind catchers' roof. The wind catchers' plan and the design of the splitting blades are different in each instance and seem to be in concordance with the general plan of the house and with the all the considerations needed for better performance. Moreover, the wind catchers sometimes have an added evaporative cooling function with a water pool positioned at the bottom. This study was initiated with a hypothesis that in all Yazd houses with wind-catchers, there is a water pool positioned underneath. A second hypothesis suggested that the area of the wind-catchers is related to the total area of the chamber to which it connects. A third hypothesis proposed that all wind-catchers face the dominant wind and that they have a Northeast-Southwest main orientation axis. All the hypotheses were rejected through this study. The relation between the chamber’s area and the relevant wind-catcher’s area were calculated with the correlation coefficient in excel software.
