As one of the arid areas of Iran, Yazd is always exposed to extreme winds with dust and shifting sands. Therefore, the architectural principles in the residential architecture of the city need be adapted to such environmental conditions in order to minimize the influence of the severe winds on the interior spaces. This study investigates the influence of storms on the interior space of the central courtyards in Yazd, constructed during the Muzaffarid, Safavid and Qajar periods using CFD simulation. Three-dimensional models were prepared via Gambit software and studied in Fluent software. The wind speed entering the computing field was equal to 26.4m/s and the Dutch wind nuisance standard NEN 8100 was applied as the comfort criterion. The results showed a relationship between the extent of the central courtyard and the impact of severe storms on it, since an increase in the area of the courtyard provides enough space for the wind flow and move around it. This feature reaches its climax if the length to height proportion increases, as the wind brings the shifting sands into large courtyards, therefore, the architects tried to provide better conditions by creating microclimates
