JPH04237801A - Two-shaft contrarotating axial turbine - Google Patents

Abstract

PURPOSE:To improve energy efficiency by recovering the energy loss generated in the stationary blade of an axial turbine. CONSTITUTION:An outer rotor 6, which has an outer rotor rotary blade 5 coaxially with an inner rotor 2 that has an inner rotor rotary blade 1 connected to the shaft of a first generator 4, and in proximity thereto, is arranged in place of a stationary blade, and the rotational force is generated on the outer rotor rotary blade 5 by an introduced gas, while the adjustment of the stream of the gas to the inner rotor rotary blade 1 is carried out. The rotational force of the outer rotor 6 is transmitted to a second generator 13, which is contracted as motive power.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to steam turbines and gas turbines, and more particularly to a biaxially rotating axial flow turbine that improves turbine efficiency.

0002

[Prior Art] Axial flow turbines, which generate power by injecting high-pressure gas (e.g. steam) onto rotor blades, have conventionally used rotor blades attached to the rotating shaft and nozzles (stationary blades) attached to the casing side. The combination adjusts the flow angle to create a smooth flow and rotate the rotor blades. Such a combination is the same in the case of a multi-stage axial flow turbine having a plurality of rotors.

FIG. 3 shows the relationship between the inner rotor rotor blade 1 and the nozzle (stationary blade) 2 fixed on the outside thereof.As gas enters from the axial direction shown by arrow A and advances in the direction of arrow B, A rotational force in the direction of arrow C is generated on the inner rotor blade 1.

0004

In the conventional device described above, the nozzle 2 has the function of adjusting the angle of gas flow, and the force generated by the nozzle 2 is applied to the casing supporting the nozzle 2 (Fig. (not shown) is simply transmitted directly to
It is a loss. The present invention was made to solve the problems of the prior art described above, and by fixing the nozzle, the power that was conventionally lost is extracted as motive power, and the axial flow turbine is designed to improve energy efficiency. The purpose is to provide.

[0005]

[Means for Solving the Problems] In order to solve the above problems, according to the present invention, an inner rotor connected to the shaft of a first generator, an inner rotor rotor blade attached to the inner rotor, , coaxially with the rotational axis of the inner rotor blade, and
an outer rotor blade disposed close to the inner rotor blade; an outer rotor having a first gear formed on its outer periphery and one end of the outer rotor blade fixed to its inner periphery; and a gear of the outer rotor. a second gear disposed in engagement with the second gear;
and a second generator coupled to the rotating shaft of the gear.

[0006]

Operation: When gas impinges on the outer rotor rotor, the outer rotor rotor functions as a conventional nozzle and rotates itself. Then, the second gear that engages with the first gear formed on the outer periphery of the outer rotor blade rotates, and the second generator connected to the rotating shaft of this second gear generates electricity and recovers the power. will be held.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below with reference to the drawings. FIG. 1 is a cross-sectional configuration diagram showing an embodiment of a biaxially rotating axial flow turbine of the present invention, and FIG. 2 is a layout diagram showing the relationship between outer rotor blades and inner rotor blades. In these figures, reference numeral 1 denotes a plurality of inner rotor blades having one end fixed to an inner rotor 2, and the inner rotor 2 is pivotally supported by an inner rotor bearing 3. 4 is a first generator connected to the inner rotor 2 and driven to rotate.

Reference numeral 5 designates a plurality of outer rotor rotor blades arranged coaxially with and close to the rotation axis of the inner rotor rotor blade 1 and having one end embedded in the inner periphery of the outer rotor 6; A first gear 7 is formed on the outer periphery of. Reference numeral 8 denotes an outer rotor bearing that pivotally supports the outer rotor 6. Reference numeral 9 denotes a second gear that engages with the first gear 7, and the second gear 9 is fixed to a gear shaft 10 and supported by a gear shaft bearing 12 provided in a gear shaft housing 11. 13 is gear shaft 1
0 via a generator shaft 14. 15 is an inlet casing fixed to one side of the gear shaft housing 11, and 16 is an outlet casing fixed to the other side of the gear shaft housing.

In the above configuration, the gas (for example, steam) introduced into the inlet casing 15 from the direction of arrow A is
After passing the outer rotor rotor 5, the inner rotor rotor 1
and is discharged from the outlet casing 16. FIG. 2 shows a velocity triangle of the outer rotor blade 5. Since the outer rotor blade 5 is rotating, the gas flow indicated by arrow A is inclined by α with respect to the axial direction. Then, by moving in the direction of arrow B, a rotational force in the direction of arrow C is generated on the inner rotor blade 1. The turbine of the present invention determines the shape of the outer rotor blades 5 according to the flow of steam on the blade surface, thereby generating rotational force in the outer rotor blades 5 and directing the flow direction toward the inner rotor blades 1. Make adjustments at the same time.

The rotational force generated by the outer rotor blades 5 causes the outer rotor 6 to rotate, and the second gear 9, which is engaged with the first gear 7 formed on the outer periphery of the outer rotor 6, to rotate. This rotation of the second gear 9 causes the generator shaft 14 connected to the gear shaft 10 to rotate, and the second generator 13 is activated. In this case, since the outer rotor blades 5 embedded in the outer rotor 6 are subjected to compressive force due to centrifugal force, the blades 5 are designed to be able to withstand buckling due to the compressive force. Further, since the outer diameter of the outer rotor 6 is relatively large, the rotation speed of the outer rotor 6 is kept low and the speed is increased by the second gear 9 to rotate the generator shaft 14. Note that the gear shaft housing 11 also serves as a housing for the outer rotor bearing 8.

Although FIG. 1 shows an example in which the present invention is applied to a single-stage turbine, the present invention can also be applied to a multi-stage turbine, in which case a larger rotational output of the outer rotor 6 can be expected. As a result, a significant improvement in energy efficiency is expected compared to the case of a single-shaft rotor with a conventional stator blade structure.

Furthermore, in the embodiment shown in FIG. 1, the gas is introduced from the outer rotor blade 5 side, but the gas is introduced from the outlet casing 16 side and is discharged from the inner rotor blade 1 side to the outer rotor blade 5 side. The structure may be such that Note that the shape of each component is not limited to the illustrated example and can be changed in various ways.

[0013]

[Effects of the Invention] As described above, according to the present invention, energy efficiency can be improved by adopting a two-shaft turbine structure that utilizes the energy loss that conventionally occurs in nozzles (stationary blades) as rotational force. You can make improvements. Also, 2
By extracting power from one shaft, it is possible to reduce the shaft span of a multi-stage rotor, and furthermore, by eliminating the need for stationary blades, it is possible to reduce the number of parts.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional configuration diagram showing an embodiment of a biaxially rotating axial flow turbine according to the present invention.

FIG. 2 is a layout diagram showing the relationship between an outer rotor rotor and an inner rotor rotor of a biaxially rotating axial flow turbine according to the present invention.

FIG. 3 is a layout diagram showing the relationship between a rotor rotor blade of a conventional axial flow turbine and a nozzle (stationary blade) fixed on the outside thereof.

[Explanation of symbols]

1 Inner rotor rotor blade 2 Inner rotor 3 Bearing for inner rotor ４　　　　　First electricity generation 5 Outer rotor blade 6 Outer rotor 7 1st gear 8 Bearing for outer rotor 9 2nd gear 10 Gear shaft 11 Gear shaft housing 12 Gear shaft bearing 13 Second generator 14 Generator shaft 15 Inlet casing 16 Outlet casing

Claims (1)

[Claims] 1. An inner rotor connected to a shaft of a first generator; an inner rotor rotor blade attached to the inner rotor;
an outer rotor blade disposed coaxially with the rotational axis of the inner rotor blade and close to the inner rotor blade; a first gear formed on the outer periphery and one end of the outer rotor blade on the inner periphery; The motor is characterized by comprising an outer rotor to which is fixed, a second gear disposed to engage with a first gear of the outer rotor, and a second generator connected to a rotating shaft of the second gear. A two-shaft, counter-rotating axial flow turbine.