APPARATUS FOR ATTENUATING THE NOISE MADE BY FLUID JETS EJECTED FROM A CONDUIT

摘要

An openwork screen is placed in the discharge plane of a conduit discharging a jet of fluid at sonic speeds, to reduce the noise. The screen can be in the form of parallel slats, radial slats or a network of slats. In the case of aircraft jets the screen is preferably removable form the discharge plane of the jet outlet conduit. To do this the screen can be constructed so that it disintegrates after a predetermined length of time or can be destroyed by explosives or other such means when required. Alternatively, the screen can be pivotally mounted on the wing so that it can be swung by hydraulic means into the discharge plane of the jet or out of the way, it can be arranged as a blind which can be drawn over the jet outlet, or it can be in the form of elements pivotally attached at one end to the conduit around its circumference and releasably connected near the center of the conduit so that the elements normally form a screen of radial slats, but when their center connection is released they splay out behind the jet.