US1853135A - Hydraulic turbine - Google Patents

Description

Patented Apr.- 12, 1932 untran- STATES PATENT? orrrca;

LEWIS FERRY MOODY, OF PHILADELPHIA, PENNSYLVANIA HYDRAULIC TURBINE Original application filed June 22,1923, Serial No. 647,048.. Divided and this application filed September 21, 1926. Serial No. 136,769. r

This invention relates to hydraulic turbines and particularly to turbinesof the impulse type in which a jet having a free surface is directed against the blades or buckets of a 5 runner. The chief object of the invention is to provide a turbine in'which the flowlines of the jet may be varied or adjusted so as to adapt the turbine to difierent conditions of head and also to serve to regulate the speed of the runner and the power developed.

Afurther object of the invention particularly in adapting the adjustable guiding means to an impulse turbine delivering a jet continuous around the runner will appear from the following description taken in connection with the accompanying drawings, in which 7 Fig. 1 is a vertical sectional a turbine illustrating oneembodiment of the invention, and

Fig. 2is a sectional view of a portion of the turbine shown in Fig. 1 taken on the line 22.

In the specific embodiment of the inven- 5 tion' shown a horizontal shaft turbine has a rotor with buckets'71 on a shaft 7 2. A volute inlet casing 74 surrounds the runner andhas stay vanes 75 across its inner neck portion. Vane rings 76 and 77 are fastened to the inner portion of the volute casing 7 4: and have inner surfaces in parallelplanes forming anozzle projecting an annular jet against the runner buckets. Between the rings 76, 77 are mounted adjustable guide 7 vanes or wicket gates 7 8 turning around axes parallel to the shaft 7 2, Each guide vane has a collar and pintle 7 9 joined in a recess in the ring casting 76 and at their opposite ends the guide vanes have collars and stems 80, car 40 rying arms 81 connected by links 82 to the 7 operating ring 83 rotatably mounted in bearing surfaces 84; of the intake casing 74 and held thereinby the annular casting 85. The volute. casing 74 is set in the concrete of the foundation F of the central pier or bridge 86 on each side of which is the draft tube passage D. The upper portion of the ring 7 6 is also provided with a flange 8'? connected to the flange 88 of a casing 89'supported from 50 the foundation F. On the other side the viewv through volute casing 7 4: is connected by the ring casting to the flange 90 of casing 91 also supported from the foundation F. The casings .89 and 91 enclose discharge spaces surrounding therrunner 70 and receiving the discharge therefrom and collecting it and directing it downward to the draft tube D.

The flow entering through the intake casing 7 4 passes through the stay vanes 7 5 which are inclined in the same direction as the whirl imparted to the flow by the volute form of the casing. This whirling flow then passes on through the adjustable guide vanes 7 8 whichare moved to the desired position according to the head and load on the turbine. The flow thus leaves the nozzle as a whirling jetrand enters the bucket .71 on eachside of the central wedge or splitter 92. The buckets 71 are cup shaped as indicated in Fig. 2 and they turn and spread and decelerate the flow and finally discharge it outward on each side into the casings 89 and 91. The annular jet is thus split in a central vertical plane and turned and discharged outward so that, there is little or no axial thrust on the shaft 7 2.

In the turbine shown the runner is of extremely small diameter having a hub.93 of only sufficient diameter to support the runner from the shaft 72; and this small diam'eter gives acorrespondingly high speed of rotation to the runner. Shroud. rings 94: may also be provided around the runner edges for additional strength.

Air may be supplied to the inside of the jets through the sleeves 95, and any desired means may be used to supply air to the outside of the jets such as the clearance space between the runner and the casings 89, 91.

These casings are formed in parts separable along ahorizontal plane containingthe shaft axis.

The invention is not confined to the specific embodiment shown but is intended tocover such modifications thereof as fall within the scope of the appended claims.

' I claim:

'1. In an impulse turbine the combination with a horizontal shaft and a rotor of the impulse type of an inlet passage having an annular orifice directing a continuous c1rcular free jet against said rotor, and adjust able means in said passage for imparting to said jet variable tangential components of flow with respect to the axis of said rotor.

2. In an impulse turbine the combination with a horizontal shaft and a rotor of an inlet casing having an annular jet forming orifice around the rotor shaft adapted to direct a free jet against the rotor, and means cooperating with said orifice for controlling the flow of liquid therethrough, comprising adjustable guide vanes adapted to impart variable tangential components to the fiow lines of the jet.

3. In an impulse turbine the combination with a rotor having buckets on each side of a central wedge, of an adjustable nozzle directing a free annular jet against said buckets, said jet having the same width during various degrees of nozzle adjustment.

4. In an impulse .turbine the combination with a rotor having buckets on each side of a central wedge, of an adjustable nozzle directing a free annular jet against said buckets, said jet being divided in a central vertical plane and turned outwardly and having the same width during various degrees of nozzle adjustment.

5. In an impulse turbine the combination with a rotor having buckets on either side of a central wedge, of a nozzle directing a free annular jet against said buckets, said jet being divided by said central wedge as it enters said buckets, and means adapted to impart variable tangential components to the flow lines of the jet.

6. In an impulse turbine provided with a rotor-having buckets on either side of a central wedge and an inlet casing having an annular jet forming orifice around the rotor shaft adapted to direct a free jet against the rotor, and means cooperating with said orifice for controlling the flowf of liquid therethrou-gh while maintaining the width :of the jet constant for at least two positions of jet control.

7. In an impulse turbine the combination with a rotor of the impulse "type having buckets on each side of a central wedge of an "inlet passage having an annular orifice for directing a continuous circular free jet against said rotor, and adjustable means in said passage for imparting to said jet variable tangential components of flow with respect to the axis of said rotor.

8. In an impulse turbine the combination with a rotor having buckets on either side of a central wedgeof an inlet passage having an annular orifice for directing a continuous circular free jet against said rotor, said jet being divided by said central wedge as it enters said buckets, and adjustable guide vanes adapted to impart variable tangential components to the flow lines of the jet.

9. In an impulse turbine, the combination comprising a rotor having buckets which discharge laterally, means for directing a free annular jet against said buckets in planes substantially at right angles to the rotor axis, and means to impart variable tangential components to the flow lines of the 'et. 1 10. In an impulse turbine, the combination comprising a rotor having buckets, means for directing a free impulse jet against said buckets in planes substantially at right angles to the rotor axis, and means adapted to impart variable tangential components to the flow lines of the jet, said variable means including an adjustable pivotal guide vane.

11. A hydraulic impulse turbine comprising a hub mounted upon a shaft and having two rings of buckets 'rojecting outwardly in opposite directions rom said hub, means forming an annular jet extending continuously around the runner periphery and a shroud ring carried by 'the buckets'which extends in one direction and a similar shroud ring carried by the buckets which extend in the other direction, said shroud rings being spaced apart at their inner edges to provide an inlet for a free jet.

12. A hydraulic impulse turbine comprising a hub mounted upon a shaft and having two rings of buckets projecting outwardly in opposite directions from said hub, a shroud ring carried by the buckets which extend in one direction and a similar'shroud ring carried' by the buckets which extend in the other direction, said shroud rings being spaced apart at their inner edges to provide an inlet for a free jet, and means adapted to impart variable tangential components to the said jet, and a turbine casing havingcircular portions disposed adjacent said shroud rings. 13. In a free-jet turbine, the combination with the rotor, of a casing; and a plurality of deflectors each spirally arranged in the casingin the path of the motive fluid so that the motive fluid shall be spirally directed into the rotor, whereby the single streams of motive fluid will form a constrained stream of similar spiral form upon the entire periphery of the rotor.

14. In a free-jet turbine, the combination with a rotor, of a casing; a cover in said casing arranged to form achamber with the rotor, the cover being provided with a sleeve which surrounds the turbine shaft in spaced relation and through which the outside air communicates with'the chamber-,- and a plurality of deflectors spirally arranged in the casing in the path of the motive fluid so that the motive fluid shall be spirally directed into the rotor, whereby the single stream of motive fluid will form a constrained stream of simi lar spiral form upon the entire periphery of. the rotor.

15. In a free-jet turbine, the combination with the rotor, of a casing; a cover in said 1 2 casing arranged to form a chamber with the rotor, the cover being provided with a sleeve which surrounds the turbine shaft in spaced relation and through which the outside air communicates with the chamber, means providing an opening adjacent the periphery of the runner, communicating with the chamber so that the air can equalize the pressure on both sides of the blades; and a plurality of deflectors-angularly arranged in the casing in the path of the motive fluid so that the motive fluid shall be spirally directed into the rotor, whereby the single stream of motive fluid will form a substantially continuous stream of similarspiral form upon the entire periphery of the rotor.

16. Inan impulse turbine, the combination with a rotor havingbuckets discharging on each side thereof, of a nozzle directing a free annular jet against said buckets and around their entire periphery, and means adapted to impart variable tangential components to the flow lines of the jet.

17. In a free jet turbine the combination with a rotor having impulse buckets, of means for directing fluid to said rotor in a direction normal to the axis of rotor rotation and adapted to impart whirl to the inflowing fluid includinga casing surrounding said rotor and a plurality of deflectors angularly arranged in the casing in the path of the motive fluid and inclined in the same direction as the whirl, said casing entirely surrounding said rotor whereby the single streams of motive fluid will form a substantially continuous stream or jet of whirling fluid upon the entire periphery of the rotor, and means whereby said jet is in free contact with air under substantially atmospheric pressure while impinging upon said buckets.

18. In a free jet turbine the combination with a rotor, of means for directing fluid to said rotor and adapted to impart whirl to s the inflowing fluid including a casing surrounding said rotor, a plurality of deflectors angularly arranged in the casing in the path of motive fluid and inclined in the same direction as the whirl, said casing entirely surrounding said rotor whereby the single streams of motive fluid will form a substantially continuous stream of whirling fluid directed upon the entire periphery of the rotor in a direction substantially normal to the axis of rotor rotation, and a cover so constructed and arranged with respect to said rotor and casing that its outermost portions lie within a surface which extends parallel to the runner axis and contains the outermost portion of said casing thereby to form a chamber withthe rotor, said cover being provided with a sleeve surrounding the turbine shaft in spaced relation thereto and through which space outside air can communicate.

with said chamber.

LEWIS FERRY MOODY.

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