الفهرس 
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Abstract
This dissertation presents the results of an experimental/communicational study of the combined effect of external environment and openings on natural ventilation and thermal comfort in buildings. The investigation was carried out on three different stages, where two different building models were investigated. One model (denoted M1)represented an open space in typical commercial buildings (e.g. office building) with multiple and identical front and rear openings. The other (denoted M1) represented a room in a typical residential building with a single opening in each of the rear walls. In the first stage, both models were subjected to a series of tests using a smoke tunnel test facility in with a view to evaluate the effect of wind orientation and opening location on the flow pattern inside the ventilated. Although, pictures of such flow patterns gave only a qualitative evaluation but were quite useful in understanding and interpreting of the experimental findings from wind tunnel measurements.
Notes from the results:
In the second stage, measurements were taken in a wind tunnel inside which turbulent wind was simulated (wind simulator). This tunnel test facility was designed and constructed with local materials and know how. Suitability of this wind simulator for the purpose of the present work was first checked through extensive testing before carrying out the main investigation on building models. This investigation consisted of two parts. The first part was concerned with tests on model M1 for the effect of the window combination and arrangement on thermal comfort in the ventilated space under different external environmental conditions (wind speed &direction) and fixed thermal load. In the second part, model M2was subjected to a series of tests in which pressure distribution on the various exposed surfaces of the building (front, rear, side walls, and window zone) were obtained for different external environmental conditions (wind speed & direction).Here also thermal comfort characteristics of the ventilated space examined for different window sizes and locations. For both models, single-sided and cross ventilation schemes were considered.
Notes of results:
In the third stage of the work, a CFD software package (ANSYS FLOTRAN version) was applied to the present problem, problem, where the above effects were predicted and compared with the experiment. Comparisons showed good agreements, indicating that the CFD techniques such as that used by ANSYS (finite element technique) are can be reliably used in this type of problems. Also, Comparisons indicated that the experimentally-obtained results can be accepted with confidence, leading to solid conclusions.
The present work gives important recommendations to architects and designer of a new buildings with regard to combination. Location and size of the openings in building front and rear facades for the best possible thermal comfort, depending on prevailing wind speed and building orientation. Thermal comfort in existing building, subject to analysis, may be improved by changing window size and location. Such improvement would be limited by the permissible changes and the prevailing wind direction. A thermal comfort chart derived in the present work should be quite useful both for designers and analysis who may be concerned with the comfort of occupants.
Finally, CFD techniques can be prove economical in problems of the building thermal comfort, saving the time and cost spent in experimental efforts, particularly if all possible conditions are to be studied.