US1399059A

US1399059A - Turbine-machine

Info

Publication number: US1399059A
Application number: US803334A
Authority: US
Inventors: Kaplan Victor
Original assignee: Individual
Current assignee: Individual
Priority date: 1913-11-26
Filing date: 1913-11-26
Publication date: 1921-12-06
Anticipated expiration: 1938-12-06

Description

V. KAPLAN.

TURBINE MACHINE.

APPLICATION FILED NOV. 26 19:5.

1,3993% Pafented Dec. 6, 1921.,

3 SHEE S-SHEET E.

.V. KAPLAN.

TURBINE MACHENE.

APPLICATION FILED NOV, 26, 1913.

Pa'ientmi Dec. 6, 1921,

3 SHEETS-SHEET 2.

V. KAPLAN.

TURBINE MACHINE.

APPLICATION FILED NOV, 26, m3.

3 SHEETS-SHEET 3.

w W g/Z" W42,

fliiorneg/ Patcntefi Deco VICTOR KAPLAN, or BRITAIN, AUSTRIA.

TURBINE-MACHINE.

Specification of Letters Patent.

Patented Bee. 6, 1921.

Application filed November 26, 1913. Serial No. 803,384.

To all whom it may concern:

' Be it known that I, VICTOR KAPLAN, of Briinn, in the Empire of Austria, have invented certain new and useful Improvements in Turbine-Machines, of which the following is a specification.

My invention relates to turbine machines of the kind generally employed as water turbines, steam or gas turbines, rotary pumps or centrifugal blowers.

The principal object of my invention is to provide a turbine machine working with high efiiciency even if the specific speed of friction losses caused by the flow of fluid passing through the runner wheels, also by discharging the fluid along the lower or base edges of the guide vanes and also by accommodating the meridianal flow of fluid from the entrance to'the discharge end of the turbine machines to the natural flow of fluid, not being forced to change its direction by means of specially curved guide surfaces, but only by a free deflection as it is hereinafter fully pointed out.

With these and other objects in view, as will more fully hereinafter appear, my invention consists of certain novel. features of construction and arrangement of guide and runner wheels for turbine machines above mentioned, hereinafter fully described, illustrated in the accompanying drawings and particularly pointed out in the appended claims.

In the accompanying drawings:

Figure 1 is a vertical section through the left hand half of the guide wheel and the runner of a water turbine in accordance with my invention.-

Fig. 2 is a plan view of the turbine, the guide-wheel-cover being removed.

Fig. 3 is a vertical section of the left hand half of a twin turbine according to my invention.

Fig. 4 is a vertical section throughthe left hand half of a modified form of a water turbine hereinafter particularly described.

Fig. 5 is a vertical section through the left hand half of a twin turbine.

To explain clearly the drawings it will be noticed that in Figs. 1,3, 4 and 5 the guide vanes S, and the runner blades S are sketched in a radial projection. Referring to the drawings, the turbine machine has connected to it a guide-wheel which may be constructed in the general manner as lmown in similar constructions for conductmg and guiding the driving means to the rotor wheel. But a special arrangement shows the guide vanes, the lower or base edges of which project over the wall of the suction pipe and if required may be extended in close proximity to the axis. To explain the term, base or lower edges it may be stated that the guiding surface of aguide blade S, (Fig. 1) is circumscribed by two axial or nearly axial edges a a, and a a, hereinafter referred to as inlet and outlet edges and by the base or lower edge (a a and the top or upper edge (a (1,). In the usual constructions the lower and top edges have not been utilized for allowing a smooth flow of fluid into the runner wheel, on the contrary a smooth discharge of the fluid along said edges of the guide vanes is a characteristic feature of my invention. For this purpose the base edges roject over the wall of the suction pipe 8 and also discharge the fluid without. shock into the runner wheel. In spite of this. these lower and top edges will not he called outlet edges. .This definition shall bereserved only for the axial or nearly axial edges of radial discharging guide blades as has been customary hitherto.

Figs. 1 and 2 showa guide wheel or distributer comprising a series of guide vanes C, of the described kind, each on a fixed pivot D (Fig. l). the upper end of which, being threaded, extends upward through the cover E, the lower end of such pivots extending downward through the horizontal flange of the suction tube '1 near the governing ring R.

The process of governing by means of movable guide vanes is the same as hitherto used in similar regulating voutrivam'es. But the described arrangenwut of the guide vanes S allows the discharge of fluid not only along the outlet edges a a,- but also along the lower edges a a Fig. 3 is amodification of said uide wheel adapted for a twin wheel. Bot the upper or top edges a, a and the lower edgesa a and also the outlet edges a, a of the guide vanes S discharge the fluid into the rotor wheel. I

Figs. 4: and 5 show' a further modification of a guide wheel, the guide vanes S thereon extending near the turbine shaft. If a single runner wheel is employed, as seen in Fig. 4 the whole quantity of fluid or the main portion of the same is discharged from the lower edges or (1,, of the guide vanes 8,. But if a twin runner wheel is employed as shown in Fig. 5 the whole quantity or the main portion of fluid is discharged both from the lower edges a a andiromthe upper edges a a of said. vanes. By such a modified form-of a distributer it is not difficult to arrange the guide blade bolts near the turbine shaft as it is sketched in Fig. 4 but I do not limit my invention, to the above mentioned guide vanes extending near the turbine axis because also guide vanes projecting only slightly over the wall of the suction pipe in connection with runner wheels hereinafter described in detail and-shown in Figs. 1, 2, 3, 4 and 5 give also satisfactory results.

The runner consisting of a series of runner blades S ri idl fastened into. .the wheel-cover plate F (Figs. 1 and 3) or into the nave N (Figs. 4 and 5) is located at a convenient distance below the lower edges of the guide vanes S A characteristic feature of my invention is the form of said wheel. Fig. 1 shows a general arrangement thereof.

The runner blades S forming spaces R and R between each other, the one set of runner spaces (R adapted for an axial or nearly axial admission, and the other set of spaces (R adapted for a radial or nearly radial admission. For this purpose the inlet edges e 6 of the axial flow runner blades R -are arranged more or less in the proximity of the lower edges a a of the guide vanes 8,, while the inlet edges e e, of the radial flow runner blades R are arranged more or less in the proximity of the outlet edges a a ofv the guide vanes. In order to explain clearly the object of myinvention I have indicated in Fig. 1 by the dotted lines L an imaginary intermediate wall forming an imaginary outer wheel rim for the runner spaces R and an imaginary inner wheel rim for the runner spaces R It will be seen that by such an imaginary division, a runner wheel of my invention is sub-divided into two well-known turbine wheels. The one type of which with the blade spaces R, approximately corresponds to a normal speed runner of a Francis turbine, while the other type with the blade spaces R nearly resembles an axial flow runner hitherto used under the name of J onval runner wheel.

For the satisfactory working of the turbine machine it is important to state that the principal aim of the wheel construction is directed by a suitable enlargement in the radial breadth'B of the axial flow runner spaces R for obtainin the aforesaid free deflection of the fluid. or this purpose the runner diameter D of the outer wheel rim K is so far increased in relation to the diameter D of the radialfiowrunner spaces R, that the quantity of fluid admitted to the axial portion of the runner wheel is greater than that admitted to the radial portion of said wheel. p

In opposition to the constructions of high speed runners hitherto used which areadapted chiefly for a radial admission (Francisturbine-wheels), a hi h speed runner of my invention ischiefly a apted for an axial .admission. Still it must be specially stated that the aforesaid radial runner spaces R form only a connecting link between my invention and the high-speed runner wheels hitherto used, and if necessary may be also quite dis ensed with as is shown in Figs. 4 and 5. y such an arrangement the runner 'wheel is provided only with axial flow blades extending from the runner nave N toward the wall of-the suction pipe T. The entrance edges e e of said blades are located at a convenient distance below the lower edges a a, of the guide vanes 5,.

Although the runner wheel in its form approaches a combination of two well-known forms of water turbine wheels (axial flow and Francis-wheels) or resembles simply an axial flow wheel, there is however a distinct difference in the method of the water sup-- ply'needed for a wheel hithertoused, and one of my invention.

1 In an axial flow wheel of the usual construction the water flows through the guide wheel chiefly in an axial direction. In my invention however, the main portion of fluid enters the guide wheel in a radial direction and is freely deflected in the guide spaces,

and flows in an axial or nearly axial direction into the runner wheel. The accompanying drawings show this new method of the flow of fluid in various modified forms.

Figs. 1 and 2 show the arrangement of a guide wheel and a runner wheel, the latter consisting of a combination of an axial and a radial flow runner wheel. The water entering centripetally between the guide vanes S, is freely deflected in the guide vane spaces and its main ortion flows in an axial or nearly axial direction, (indicated by the arrows 2) into the axial flow runner spaces R Only a smaller portion of fluid has not been materially deflected and flows in nearly the same radial direction (indicated by the arrows 1) into the radial flow runner spaces B The fluid having transferred its drivin power. into the runner wheel, flows 0 through the suction tube T to a Wastechannel.

' In order to increase the quantity. of water needed for the turbine machine, I have-constructed a twin turbine as is shown in Fig. 3. The twin runner wheel of such a turbine consists generally of a doubling of'the aforesaid runner wheel (Fig.1). Opposite to the blade space R there is an identical or nearly identical blade space R The water entering the guide wheel in a radial direction is freely deflected between the guide vanes thereon and flows not only along the lower edges (1 a, and the outlet edges'ol. (1 but also along the upper edges a a, into the runner wheel as indicated by the arrows 3.

If the whole quantity of water entering the guide wheel is to be deflected from its radial entrance direction for the 'purpose of an axial or nearly axial inlet intothe runner wheel, the runner wheel should have single blade spaces R, as shown in Fig. 4. The free deflection of the water in the guide spaces is indicated by the arrows 2.

But I do not limit my invention to the guide vanes extending near the turbine shaft and indicated in Fig. 4 because guide vanes projecting only slightly over the wall of the suction tube in connection with a runner wheel of, the above description give also satisfactory results. In such a case the water leaves the guide vanes also along the outlet edges and its free deflection is continued in the clearance betwen the guide vanes and the runner blades.

A runner wheel indicated in Fig. t may be also doubled, if the supply of water is much increased.

Fig. 5 showssuch a twin turbine. Thev uide wheel of which discharges the water both along the lower edges a, a, and the upper edges (1, a as indicated by the

arrows

2 and 3. For this purpose two runner spaces R and R adapted for an axial or nearly axial admission are arranged near said edges. It is evident, that a satisfactory working may also be obtained by the arrangement of guide vanes projecting only slightly over the wall of the suction pipe as is clearly explained above.

In order to make clear the importance of the axial runner spaces itmay be explained, that only by the arrangement of such spaces a free deflection of the radial flow of fluid is to be obtained, as can be seen from the following explanation.

faces. Nevertheless the flow through the tube is in an approximately axial direction.

For this .reason it is evident that this natural flow of fluid should be interruptedas little as possible. But this natural flow of fluid should not disturbedby a special curvature of the wheel cover plate P as hitherto employed. In my invention this requirement is supplied by the aforesaid arrangement is axial flow runner spaces R (Figs. 1, 2, 3, 4 and 5), which are so enlarged in their radial breadth that the major portion or the whole quantity of fluid can flow through the said spaces, and therefore the wheel-cover plate P (Figs. 1 and 3) can be so much reduced in its radial extension, that its form and curvature do not influence the above mentioned natural flow of fluid through the turbine machine. Moreover by such an arrangement of axial flow runner spaces, the inlet of fluid into the'runner" wheel is also facilitated, because the guide vanes are thus enabled to project materially over the wall of the suction pipe. For this reason suchvanes discharge the water also along their lower edges into the runner wheel.

, It is not diflicultto provide such a curvature of the lower edges of the guide vanes that the fluid admitted to the axial flow runner spaces can flow into said spaces without movable in the usual manner, could not be closed entirely. In my invention however the curvature of the lower edges a, a and the size of the outlet angles thereof can be accommodated to a smooth inflow (without shock) into the axial runner spaces, as is shown in Fig. 2. Nevertheless the closing of the guide passage is complete even if the guide vanes are movable in the usual manner. A further advantage obtained by such a combination consists in reducing the loss b friction of fluid caused'by the runner blades and the wheel cover plate P. If said parts rotate at a high speed, it is evident that said losses are as much'increased as the Cir close proximity to the turbine shaft, because in'the neighborhood of said shaft the relative velocity between the guide surfaces and the flowing fluid is slight even with a high number of revolutions of the runner wheel. It will be seen from Fig. 1 that bysuch an arrangement only the outermost portions of the axial flow runner spaces R are influenced by a great relative velocity, while the radial flow spaces in their full axial extension liein a zone of much reduced relative velocity. For this reason the friction of fluid caused by the wheel cover plate P (Fig. 1) is also reduced, because its outer diameter can be thus diminished. A further reduction of said friction losses can be obtained by nearly or completely removing the radial runner spaces R as will be seen from Figs. 4 and 5. By such arrangement therefore the wheel cover plate shrinks to a runner nave N, and it is evident that the friction losses caused by such a nave are still more reduced.

Another advantage of the above described arrangement is that it provides a runner wheel of a strong construction. It is evident that the runner blades running at very high speed are much affected by the centrifugal forces. Any tendency to alter the form of said blades by the influence of such forces will best be counteracted by extending said blades in a radial or nearly radial direction. An arrangement of this kind requires generally a series of axial flow runner blades and for this purpose a runner wheel adapted for an axial or nearly axial admission indicated by the Figs. 4 and 5 is enabled to run at the highest possible specific speed, without getting .in danger of being disturbed by the influence of centrifugal forces. Although the wheel .construction of high speed runners hitherto used shows a radial or nearly radial dmission, I have shown by the above men tioned reasons and tested by hydraulic experiments that the efficiency and the specific speed of a runner wheel chiefly adapted for an axial admission and provided with a free deflection of water flow is superior.

It 'will be well understood that various changes in the form, proportions, size and minor details of the structure of my invention may be made without departing from the spirit, or sacrificing any of the advantages above described.

In the specific. examples illustrated I have shown a series of water turbines in their most simple form, comprising a guide wheel which resembles the construction of a distributer for Francis turbines. The guide vanes thereon movable in the usual manner and their edges sketchedin the radial projection as straight lines. But guide vanes rigidly fastened in the turbine casing give also satisfactory results even if the edges of the guide blades are curved. Also it isgen- 'vature of the guide wheel cover E (Figs. 1

era ly not necessary to shape the entrance edg s e e, of the axial flow runner blades as it straightline extending in a radial direc' tion from the nave toward the suction tube, as is indicated by Fig. 5. It will be seen from Fig. 4: that said edges also may be curved as long as the main portion of water is still admitted in a nearly axial direction. Such a curvature of the entrance edges therefore should be adopted, if the turbine wheel works under a high pressure of water. It is evident, that in such a case these parts of runner blades adjacent to the runner nave are under much stress due to bending'from water pressure. In such cases I prefer to increase the axial breadth of the runner blades toward the runner nave by curving the entrance edges thereon upward an toward said nave. Also the form and ourand 4) have no influence on the good working of the turbine machine, so long as the free deflection of water is not disturbed. A water turbine with a guide wheel and a run-' ner wheel of the kind described, may be utilized everywhere and particularly for high specific speeds. It is well known, that many water-courses cannot be utilized for the reason, that the number of revolutions is too small, and low specific speeds require expensive machinery and buildings. By the use of my invention however the erection of a turbine plant is economical, even if the employment of high speed runners of the form hitherto used in the construction of such plant would be too expensive.

Having ascertained the advantages obtained by adopting axial flow runner spaces of the kind described it is evident, that such a combination of a distributer and a runner wheel can also be utilized for steam and gas turbines, if the guide and runner spaces are accommodated to the gaseous nature of the driving agent.

While I have described my invention as applied to prime movers, it will be understood that I do not consider it to be limited thereto, but contemplate applying it to pumpin apparatus also.

aving thus fully described my invention, what I claim as new, and desire to secure by Letters Patent is 1. In a turbine machine the combination of a guide wheel, the guide vanes thereon projecting over the wall of the suction pipe, and a runner wheel c mprising a series of runner blades forming spaces between each other, the one set of runner spaces adapted chiefly for an axial admission and arranged near the lower edges of the guide blades, the other set of runner blades adapted chiefly for a radial admission; the fluid entering the guide wheel centripetally being freely deflected between the guide vanes, and the 'quantity of fluid admitted to the axial portion of runner wheel being greater than the quantity-admitted to the radial portion of said wheel.

2. In a turbine machine the combination of a guide wheel, the guide vanes thereon projecting over the wall of the suction pipe, and a runner wheel comprising a series of runner blades, forming spaces between each other, one set of said runner spaces adapted chiefly for an axial admission and arranged near the lower edges of the guide vanes, another set of axial flow runner spaces arranged near the upper edges of said guide vanes and a third set of runner spaces adapted chiefly for a radial admission, the fluid entering centripetally between the guide vanes being freely deflected in the guide spaces and the quantity of fluid admitted to the axial portion of the runner being greater than the quantity admitted to the radial portion of said wheel.

3. In a turbine machine, the combination of a guide wheel, the guide vanes thereon projecting over the wall of the suction pipe, and a'runner wheel comprising a series of runner blades forming spaces between each other adapted for an axial or nearly axial admission and arranged near the lower edges of the guide vanes, the fluid entering centripetally between the guide vanes being freely deflected in the guide spaces and How ing in an axial or nearly axial direction into the runner wheel.

4:. In a turbine machine, the combination of a guide wheel, the guide vanes thereon projecting over thewall of the suction pipe and a runner wheel comprising two sets of runner blades forming spaces between each other, adapted chiefly for an axial admission, the one set arranged near the lower edges of the guide vanes andthe other set arranged near the upper edges of said vanes, the fluid entering centripetally between the guide vanes being freely deflected in" the guide spaces and flowing in an axial or nearly axial direction into the runner wheel,

5. In a turbine machine the combination of a distributer for Francis turbines, and a runner wheel comprising a hub and a series of axial-flow blades arranged around said hub and rigidly secured therein extending in a direction the major component of which is radial toward the wall of the suction pipe, the guide vanes projecting over the wall of said suction pipe the lower edges and the outlet edges of said vanes being open to the runner wheel and discharging the fluid into the runner blades.

6. In a turbine machine a runner wheel forming a combination of a Francis wheel and an axial-flow wheel, the quantity of fluid admitted to the axial portion of the runner being greater than the quantity admitted to the Francis wheel, a guide wheel for Francis turbines provided with guide 'vanes, projecting over the wall of the suction pipe, the lower edges and the outlet edges of said vanes being open to the runner wheel and dischargingfthe fluid into the runner blades. j

7. In a turbine machine the combination 0f a distributer for Francis turbines, the guide vanes thereon projecting over the wall of the suction pipe, and a runner wheel compr sing a hub, two series of axial or nearly axial-flow blades arranged the one near the lower and the other near upper edges of the guide blades and rigidly secured into the runner hub, the lower, the upper and the outlet edges of said blades being open to the runner blades and discharging the fluid into the runner wheel.

8. In a turbine machine a runner wheelforming a combination of a Francis wheel and two axial-flow wheels, the one arranged near the lower edges of the guide vanes, and the other near the upper edges of said vanes, a distributer for Francis turbines, the guide vanes thereon projecting over the Wall of the suctlon pipe, the quantity of fluid admitted to the axial portions of the runner wheel being greater than the quantity admitted to the radial portion of said wheels.

9. In a turbine machine the combination of an impeller and a guide wheel, the former consisting of a hub and a series of axial-flow blades arranged around said hub and rigidly secured therein extending in a direction the major component of which is radial toward the Wall of the suction pipe, and the guide vanes projecting over the wall of said suction pipe, the fluid flowing through the impeller chiefly in an axial direction, is freely deflected to the guide spaces, and leaving the guide Wheel in an axial or nearly axial direction.

10. In .a turbine machine the combination of a guide wheel, the guide vanes thereon projecting over the wall-of the suction pipe,

and an impeller comprising a series of impeller blades forming spaces between each other, the one set of impeller blades adapted chiefly for an axial flow and arranged'near the lower edges of the guide blades, the other set of impeller blades chiefly adapted for a radial flow, the quantity of fluid discharged to the axial portion of the impeller being greater than the quantity discharges to the radial portion of said impeller.

11. In a turbine machine the combination of a guide Wheel, the guide vanes thereon projecting over the Wall of the suction pipe, and an impeller comprising a series of impeller blades forming spaces between each other, one set of said impeller spaces adapted chiefly for an axial flow and arranged near the lower edges of the guide vanes, another set of axial flow impeller spaces arranged near the upper edges of said guide vanes, and a third set of impeller spaces adapted chiefly for a radial flow, the quantity of fluid discharged to the axial portion of the impeller being greater than the quantity discharged to the radial portion of said impeller. v

12. In a turbine machine the combination of a guide wheel, the guide vanes thereon projecting over the wall of the suction pipe, and an impeller comprising a hub, two series of chiefly axial flow blades arranged near the lower and the upper edges of the guide vanes and rigidly secured into the impeller hub, the fluid flowing through the impeller chiefly in an axial direction being freely deflected into the guide spaces and leaving the guide wheel in an axial or nearly axial direction.

13. In a turbine machine, the combination of guide blades, and runner blades forming spaces between each other contiguous to the radial edges and to the axial edges of said guide blades, the spaces contiguous to the radial edges being relatively large whereby the passage of the greater part of the motive fluid takes place between the radial edges, said guide blades and runner blades being so arranged that the direction of flow changes freely from either the radial to the axial or the reverse according to the direction of flow.

14:. A turbine machine comprising in com bination a runner provided with axial flow blades, guide blades arranged to extend in a generally radial direction with respect to the axis of said runner and extending from the outer edges of the runner blades toward the axis of the runner, the radial edges of the guide blades being open to the runner blades and contiguous thereto whereby the fluid is free to change its direction in the guide space in passing through the machine, said guide blades being curved in the radial direction whereby the fluid passes through the machine without shock.

15. A turbine machine comprising in combination a runner provided with axial flow blades, guide blades arranged to extend in it generally radial direction with respect to the axis of said runner and extending from the outer edge of the runner blades toward the axis of the runner, the lower edges of the guide blades being open to the runner blades and contiguous thereto whereby the fluid is free to change its direction in the guide space in passing through the machine, said guide blades being so formed as to present cylindrical surfaces to the fluid, the elements of said cylindrical surfaces being parallel to the axis of the runner and the blades being curved in the radial direction whereby fluid passes through the machine without shock.

In testimony whereof I have signed this specification in the presence of two subscrib ing witnesses.

VICTOR KAPLAN.

Witnesses:

GRAUNER KARL, ADA MARIA BERGER.