GB860994A - Fluid flow control devices - Google Patents

Abstract

860,994. Regulating fluid flow. KANTROWITZ, A. June 5, 1957, No. 17937/57. Class 135. A fluid flow control device, without moving parts, which permits flow through a conduit readily in one direction but retards flow in the reverse direction, comprises a conduit 10 with a core 13 extending lengthwise thereof and spaced from the wall of the conduit, and cascades 20 of blades 21, 22, 23, 24 and 25 within this space, the blades being of limited angular extent about the longitudinal axis of the device and the cascades being angularly spaced so as to leave open, unobstructed passages 28 between the cascades for the flow of fluid through the device, the blades of the cascades having generally concave faces on their sides toward the downstream end 16 of the device and being shaped and positioned to produce circumferential components of flow in the event of back flow so as to retard the back flow. As shown, the angular spacing of the cascades is greater than the angular extent of the blades and the cascades are parallel to the axis of the conduit; they may alternatively be given a slight helical angle (Fig. 4, not shown). The first few blades 22 to 25 at the downstream end present progressively greater angles to the longitudinal axis for imparting circumferential flow in the event of back flow. The leading edges at least of the blades, with respect to the circumferential flow, are swept back radially (Fig. 3). The device may be applied to pulse jets or in other fields where the use of moving mechanical parts is objectionable or inconvenient.