Importance of natural ventilation in residential properties and its evaluation in relation to windcatchers under today's conditions

Strucrtures have been playing important roles in different areas of people's lives such as community health aspects and their comfort needs since their creation in earlier times of man made building history. The quality of air circulation and conditioning is one of the most important factors in the context of designing healthy spaces for our daily life. This is why many architects concern about energy efficiency and air circulation/condition aspects as they generally tend to design sustainable structures in recent years. Today we have to take care of our energy resources as they are not renewable in the limited times and so their capabilities don't fullfill the speed of our consuption rate specially for last decades. So the tendency for designing energy efficient buildings and using of structural elements which are designed according to geographic and weather conditions of a building are important aspects of design which are being considered by many of designers. Genarally the trend includes the use of opening elements of the structure such as doors, windows, funnels and any other specially designed opening elements to let the clean air passes through all of the essential areas. The air movement and circulation occures as a natural result of temperature diversity between indoor and outdoor areas and the differentiating pressure of them which pushes the clean air into the building. Natural air conditioning has been one of the oldest and most popular air circulating systems from centuries ago. It is important to achieve nature based solutions to provide sustainable living conditions in architecture. Many of old patterned dwellings have been rationally designed in accordance with the local weather and topography of their locations in a genius way. Badgir or windcather, one of these structures which generally has been designed as an architectural element parallel to its functional role as an air conditioning element in the most of middle eastern countries and specially in Iran, is the main subject of this study. There are different types of Badgirs (wind cachers) within defined range of weather conditions according to their functions. In this thesis in the context of designing natural air conditionig systems as an essential need for sustainable architectural design, the structure of different types of Badgirs (windcatchers) and many analysis have been studied and an evaluation on a recent proposed system for improving the performance of Badgirs (wind catchers) has been made. The study includes six chapters: Chapter 1; Entrance, the purpose of the study, literature study and hypothesis. Chapter 2; A glance into natural air conditioning systems, principles, methods and their effects in architecture. Chapter 3; History of Badgirs (windcatchers) or windcatchers in the Middle Eastern countries. Chapter 4; Reserching the dry/hot and wet/hot weather of two cities of Iran, analysing different types of Badgir (wind catchers) structures. Analysing historical and modern systems through Bagdir samples and exploring a new improving method for thr performance of Badgirs (wind catchers). Chapter 5; Includes the conclusion of this research. In this chapter the data through all the progress has been summarized and the contemporary windcatcher samples has been compared to the traditional ones in the context of their microclimatic aspects and evaporating effects.