Abstract: An air flow measurement device includes a connector conduit with a constant inner diameter wall for the air flow, a transverse restrictor plate located within the conduit with a plurality of generally uniformly spaced apertures extending therethrough, and an annular mounting piece secured centrally about the conduit for securely mounting a pair of air pipes to the opposite ends of the conduit in air-tight engagement therewith. The restrictor plate is maintained in the connector conduit by a swaging operation which causes it to be expanded outwardly into tight engagement with the conduit wall. A pair of tank valves are mounted, by a special saddle, to the mounting piece, and passages are provided through the mounting piece and conduit wall for communication with the interior of the conduit just upstream and downstream of the restrictor plate whereby a differential pressure meter may be connected to the valves to measure the difference in pressure to thereby determine the air flow rate.

Abstract: An optical fiber sensor for inducing a microbend in an optical fiber in the presence of the liquid phase as distinguished from the vapor phase of a fluid such as water. The sensor includes a chamber with an expansible block located therein, and a thin band is provided about the block of a dimension and tensile strength such that any increase in outward expansive force in the block due to an increase in the presence of the fluid in its vapor phase only will not cause the band to rupture; however, when any liquid enters the chamber, the band will rupture to allow the block to expand in a particular direction to move a pusher bar which, in turn, moves a puller wire to bend the fiber at a location remote from the chamber.

Abstract: An optical fiber sensor for inducing a microbend in an optical fiber in the presence of a detectable fluid such as water includes a chamber with an expansible block located therein. When water enters the chamber, the block expands in a particular direction to move a pusher bar which, in turn, moves a puller wire to bend the fiber at a location remote from the chamber. A gap may initially be provided between the expansible block and the pusher bar so that the presence of water vapor within the chamber will not move the pusher bar but the presence of liquid water will.