GB805463A - Improvements in the control of fluid flow - Google Patents

Abstract

805,463. Liquid, gaseous or pulverulent fuel burners. FUEL FIRING, Ltd., and WEBB, E. F. D. Nov. 2, 1955 [Sept. 8, 1954], No. 26078/54. Class 75(1) [Also in Group XXIX] For varying the flow of fluid through a conduit e.g. a burner, a series of radially disposed juxtaposed flexible vanes mounted at their leading and trailing edges transversely of the direction of fluid flow in the conduit are operably controlled during the fluid flow for varying the curvature of the vanes. The arrangement shown in Figs. 1 and 4 comprises a series of resilient radial vanes 11, attached at their trailing edges to pins 21 mounted in ball and socket joints 22 in a housing 20 and at their leading edges to radial arms 10 of a spider 9 attached to a slidable sleeve 7. The curvature of the vanes 11 is altered by moving the sleeve 7 towards or away from the burner mouth by fluid pressure acting on pistons 14 attached by rods 13 to a plate 12 connected to the rear end of the sleeve 7. 'The vanes 11 on movement in the direction of arrow A, Fig. 4, are bent from the form shown at B to the form shown at C thus varying the area of discharge of secondary air and altering from B to a the angle at which the air is discharged into the cambustion zone. The air supply to the burner enters through openings 25 in a casing 23 attached to the furnace wall 24 and is divided into two streams one stream, the primary air, passing through slots 8 in the sleeve 7 and slots 5 in an inner sleeve 1 to a position where it is deflected towards the burner tube 2 by a conical flange 6 on the sleeve 1 and the other stream, the secondary air, passing between the vanes 11. Axial movement of the sleeve 7 also varies the primary air supply to the cambustion zone by altering the alignment of the slots 8, 5. The housing 20, slidably mounted within the casing 23, is supported on a tube 18 attached to a back plate 17 normally held against the casing 23 by suitable locking means so that when the locking means are released the housing 20 can be drawn into the casing 23. A fuel control valve 27 mounted at the rear of the sleeve 1 is operated by a control lever 30 which lever when in the operative position engages a collar 3 on the tube 2 to lock the tube 2 in position and when in the inoperative position shuts off the fuel supply and disengages the collar 3 so that the tube 2 can be removed. A pre-set primary-secondary air ratio can be effected by rotating the sleeve 1 by a handle 32 to vary the alignment of the slots 8, 5. In a modified arrangement, shown in Fig. 5 a set of fixed radially disposed vanes 11a are aranged at the forward end of the sleeve 1 and the adjustable vanes 11 are aranged around the fixed vanes 11a.