FLUID CONTROL DEVICE WITH REDUCED SOUND GENERATION

摘要

A fluid control device with a reduced sound generation. The device is a nozzle-type valve that has a converging portion, a diverging portion and a throat therebetween. A diverging portion acts as a diffuser and may be conical or may have a slight curvature. In each, the diffusion angle is less than 20° so that turbulence of fluid flowing through the valve is minimized and a boundary layer is maintained between the fluid and an inside surface of the fluid control device. A control system that uses such a fluid control device is also disclosed and such device may be used either in a supply conduit or an exhaust conduit.