A system for producing variable amplitude pneumatic pulses, such as may be used to prevent flow separation on airfoil and diffuser surfaces to control stalling, utilizes a source of pressurized air... Show moreA system for producing variable amplitude pneumatic pulses, such as may be used to prevent flow separation on airfoil and diffuser surfaces to control stalling, utilizes a source of pressurized air which is regulated and fed to parallel outlet lines. Each outlet line has a control valve therein attached to a controller for activation of the valves. The first parallel line leads to an actuator which supplies the pulsed air to a desired surface. The second parallel line leads to the atmosphere. By cycling the valves at about ninety degrees out of phase, pneumatic pulses of large amplitude are obtained with a simple device capable of being transported on the aircraft. Show less
