US1389910A - Multistage axial-flow steam or gas turbine - Google Patents

Description

P. SPIESS.

MULT ISTAGE AXIAL FLOW STEAM 0R GAS TURBINE. APPLICATION FILED MAR. 31. 192].

1, 389,910, PatentedSept. 6, 1921.

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PATENT OFFICE.

PAUL SPIESS, OF ZIl'RICI-I, SWITZERLAND.

MULTISTAGE AXIAL-FLOW STEAM OR GAS TURBINE.

Specificationof Letters Patent.

Patented Sept. 6, 1921.

Application filed March 31, 1921. Serial No. 457,343.

(GRANTED UNDER. THE PROVISIONS OF THE ACT OF MARCH 3, 1921, 41 STAT. L, 1313.)

T 0 all whom it may concern:

Be it known that I, PAUL Srmss, a citizen of the Republic of Switzerland, residing at Zurich, Switzerland, have invented certain new and useful Improvements in Multistage Axial-F low Steam or Gas Turbines, (for which I have filed applications in Switzerland, Feb. 6, 1917, Patent No. 76,010; England, Jan. 31, 1918, Patent No. 113,273; Germany, Feb. 10, 1917, utility model 681,589; France, Jan. 23, 1918, Patent No; 188,588 and I do hereby declare the following to be a clear, full, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawing, and to letters or figures of reference-marked thereon, which form a part of this specification.

This invention has reference to guide channels for multistage, axial flow steam or gas turbines adapted to direct the driving medium from one rotor wheel or runner to another rotor wheel or runner having a considerably difl'erentdiameter. In a turbine according to the invention a guide channel of S-shaped longitudinal section in a plane passing through the turbine axis with an entirely axially directed inlet and an entirely axially directed outlet for conveying the driving medium from one rotor wheel to a similar one of considerably different diameter has arranged within it at least one partition or guide wall corresponding to the said sectional shape of the channel, the rotor wheels being of the usual type the blades of which extend without obstruction from the rotor disk periphery to the bounding rings, the arrangement being such that the total quantity of steam or gas working on the blades of one rotor wheel is guided over to the blades of the next following rotor wheel in such-wise that all the steam entering the said next ring of blades is directed axially as far as possible, and thus possesses a radial component as low as possible. The said partition or guide wall may in some cases extend only over the first portion of the length or" the channel.

In guide channels which have to direct the driving medium from one rotor wheel to another having a considerably different mean diameter, for instance a considerably greater mean diameter, and into which the driving medium disturb each other when the direc-' tion of the middle line of the channel, seen in longitudinal section, in a'plane passing through'the turbine axis, changes, and that said layers cause eddies and lower consequently the eiiiciency of the turbine.

This drawback is largely remedied by the present invention.

1 am aware that it has already been proposed to provide in steam turbines annular guide walls for separating into annular portions the steam flowing from a number of rows of moving blades to the exhaust and also for guidingand separating into annular portions the steam flowin from a portion of one set of moving blades to another set. In contradistinction to such a construction however each current of steam that has done duty in the moving blades of one rotor wheel is, according to the present invention, guided completely to the moving blades of 'the next following rotor wheel, care being taken that such steam strikes the said moving blades in an axial direction, that is to say the current of steam has as small a radial component as possible when it impinges on the said blades.

The accompanying drawing illustrates diagrammatically two embodiments of the invention. The two figures represent longitudinal sections in a plane passing through the turbine axis through the parts carrying the blades of a steam turbine comprising six pressure-stages and in which the three last stages have a considerably greater mean wheel-diameter than the three first stages. Into the intermediate guide channel are inserted guidewalls. The steam flows from the left to the right hand side.

In Figure 1, it will be seen that the rotor wheels 1, 2 and 3 have approximately the same mean diameter d and that the rotor wheel a, has a diameter D, the latter being considerably greater than the diameter (Z. Within the intermediate guide channel 7 is arranged a guide wall 8 extending over the entire length of the channel.

According to the embodiment shown in Fig. 2, three guide walls 13, 14 and 15 are provided only on the first portion of the uide channel 12 in theintermediate disk 11.

' zlompared' with the construction shown in Fig. 1, said shorter walls offer the advantage that they oppose less frictional resistance to the steam flowing through the channel. In spite of their shortness, they are yet able to guide the steam in a sufiiciently satisfactory manner.

It is obvious that before entering the rotor wheels at the end of the S-shaped channels,

the steam will be suitably directed by means of guide blades'arranged in these channels. a I claim:

1. In a multistage axial flow steam or gas turbine having a guide channel S-shaped 'in'longitudinal axial section for conveying the driving medium from one rotorwheel to a similar one of considerably diflerent diameter; a partition or guide wall arranged within this channel, said partition having a form corresponding to the sectional shape of the channel, the rotor wheels being of the usual type having blades that extend without obstruction from the rotor disk peripheryto the bounding rings, whereby the total quantity of steam or gas working on the 7 blades of one wheel is guided over to the blades of the next following rotor wheel.

2. In a multista e axial flow steam or as turbine having a guide channel S-oshaped J in longitudinal axial section for conveying the driving'medium from one rotor wheel to a similar one of considerably diiferent d1- ame'ter, said channel having an entirely axially directed'inlet and an'entirely axially directed outlet, a partition or guide wall arranged within said channel, said partition? having a form corresponding. to the sectional shape of the channel, the rotor wheel being of the usual type having blades that a similar one of considerably different di-' ameter, saidchannel having-an entirely axially directed inlet and an entirely axially directed outlet, apartit-ion or guide wall arranged within said channel and extended. only over a portion of said channel, said par tition having a form corresponding to the sectional shape of the channel, the rotor wheel being of the usual type having blades that extend without obstruction from the rotor disk periphery to the bounding ring, whereby. the total quantityv of steam or'gas working on the blades of one rotor wheel is guided over to the: blades of the next follow.

ing rotor wheel to cause allthe steam entering: the said next ring of blades to be directedaxially as far as possible 'andthus pos- In testimony that- I claim the foregoing as my nvention, I'have signed my name.

PAUL 'srrnss.

,sesses a radial component as low as possible.

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