Centrifugal fans are mechanical devices designed to move air or gas by converting rotational energy into kinetic energy. They consist of a rotating impeller that draws air in through the center and expels it at a right angle through a duct. This design allows for efficient airflow and is commonly used in various applications, including heating, ventilation, and air conditioning systems, as well as in industrial processes. These fans are characterized by their ability to generate high pressure and are often used in situations where air needs to be moved over long distances or against resistance. They come in various sizes and configurations, making them suitable for both residential and commercial use.