A Venturi valve is a type of flow control device that is used to regulate the flow of a fluid in a pipe or duct. It works by using the Bernoulli principle, which states that when a fluid passes through a constricted area, its velocity increases and its pressure decreases. This creates a vacuum in the constricted area, which then draws in more fluid from the upstream side. The Venturi valve is composed of a converging section, a throat, and a diverging section. The converging section increases the velocity of the fluid, while the throat maintains a constant cross-sectional area. The diverging section then reduces the velocity of the fluid and increases its pressure. The Venturi valve is used in a variety of applications, such as regulating the flow of water in a sprinkler system, controlling the flow of air in a pneumatic system, and controlling the flow of fuel in an engine. It is also used in medical applications, such as controlling the flow of oxygen in a ventilator. The Venturi valve is an efficient and reliable way to control the flow of a fluid in a pipe or duct.