- fitting or device that consists of a tube constricted in the middle and flared on both ends; a fluid’s velocity will increase and a fluid’s pressure will decrease while passing through the constriction; placing a tube or pipe at the constriction point creates a vacuum; fluid or air can then be drawn in through the tube; a hydrotherapy jet draws air in and mixes it with the water using this principle
- increasing water velocity by restricting pipe size
