| 摘要 |
<p>712,051. Elastic-fluid turbines; axial-flow compressors. ROLLS-ROYCE, Ltd. Oct. 9, 1952 [Oct. 10, 1951], No. 23637/51. Classes 110(1) and 110(3) In axial-flow machines having bladed rotors and stators together with tapping means for drawing off through the rotor drum part of the pressurized fluid flowing in the fluid channel of the machine, the tapping means comprises stator guide vanes 23 which are located radially inwards of the stator blading 11 and are adapted to impart a whirl in the direction of the rotor to the fluid entering the said rotor drum. The guide vanes 23 are brazed to the flanges 20 of the stator blades 11 and to a ring 27. The rotor drum 13 has blade-carrying discs 14 which are splined thereto and separated by a spacer 19 having circumferentially elongated slots 24 for directing the withdrawn fluid into rotor guide vanes 25 carried by the disc 14. The ends of the slots 24 are chamfered so that the walls there-between are inclined. The guide vanes 25 are formed from channel-section strip and are curved so that the flow therebetween is a free vortex whilst the circumferential velocity adjacent the shaft 13 is the same thereas. The vanes 25 are spot welded to discs 28, 29 which have turnedover outer peripheries, the disc 29 being secured to a ring 30 splined to the shaft 13. The vanes 23 make an angle of 80 degrees to the adjacent tangent at their inlet ends and an angle of 48 degrees to the adjacent tangent at their outlet ends and are outwardly concave and inwardly convex. In a modification the convex and concave surfaces of the vanes 23 are outwardly and inwardly facing respectively. In a second modification, the guide vanes 25 are radial to define a forced vortex flow therebetween, the vanes 23 being similar thereto. In a third modification, Fig. 4, the vanes 25 are omitted and the blade-carrying discs are spaced apart by spacer rings 32 through which extend bolts 33, strengthening rings 34 being provided as shown, On a further modification. the axial spacing between a pair of adjacent discs 14 is relatively large compared with the dimension of the slots 24 axially of the machine and the slots 24 are arranged, in the axial sense, substantially symmetrical with respect to the two discs. The ports 22 are also symmetrically disposed with respect to the two discs whereby the central layer of air in the space between the two discs is drawn off with a free vortex motion. Specification 622.181 is referred to.</p> |
