The Venturi effect describes the phenomenon where a fluid, such as air or water, accelerates as it passes through a constricted section, resulting in a decrease in pressure. This occurs because the fluid is drawn into the narrower area, and the increase in velocity leads to a corresponding drop in pressure. The effect is named after Giovanni Battista Venturi, who first articulated this principle in 1797.
A perfect example of the Venturi Effect can be found in our Air Amplifiers. Compressed air enters through the air inlet and flows into an annular chamber, where it is accelerated through a small ring nozzle. This high-velocity primary airstream follows the Coanda effect, guiding it toward the outlet. As a result, a low-pressure zone forms at the center, drawing in a significant volume of surrounding air into the primary flow. The mixture of the primary airstream and the surrounding air is then expelled from the Air Amplifier at a high volume and velocity.

The Venturi Effect is represented in amplification ratios. A ratio represents the relationship between two quantities, indicating how many times one value is contained within another. In the case of the Super Air Knife, this ratio illustrates the volume of ambient air that is drawn in alongside the primary flow of compressed air. With an impressive amplification ratio of 40:1, the Super Air Knife incorporates 40 parts of ambient air for every single part of compressed air, making it one of the most efficient air-operated knives available. This addition of mass enhances the device’s ability to deliver a powerful force, enabling it to perform more effectively in various applications.

The Venturi effect is integral to various EXAIR products designed for cooling, drying, and cleaning, alongside our vacuum generators. If your facility has a process that could benefit from an Intelligent Compressed Air solution, please reach out to us. We would be pleased to discuss your specific application and develop a solution that not only lowers your compressed air expenses but also enhances worker safety.
Jason Kirby
Application Engineer
Email: [email protected]
Twitter: @EXAIR_jk