GB2070689A

GB2070689A - Gas turbine engine

Info

Publication number: GB2070689A
Application number: GB8007056A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-03-01
Filing date: 1980-03-01
Publication date: 1981-09-09
Also published as: GB2070689B

Abstract

The engine has a rotor in which compression, combustion and expansion take place whilst the working fluid is being rotated, fuel being mixed with air and burnt in one or more combustion passages, the blades 5 of the centripetal turbine extending from the periphery to points nearer to the axis of rotation than the blades 4 of the centrifugal compressor. A vacuum may be maintained between the rotor's outer wall 3 and a stationary casing 11. <IMAGE>

Description

SPECIFICATION Gas turbine improvements (Part 2) This invention relates to gas turbines, its object is to improve the efficiency of the working cycle whereby heat energy from the internal combustion of a fuel may be converted into mechanical energy.

According to the present invention, the gas turbine comprises a centrifugal compressor, a radial inward-flow turbine, lateral passages through which the working fluid passes from the compressor outlet to the turbine inlet and means for injecting, igniting and burning a fuel in one or more of the said passages at constant pressure, the whole assembly being fixed together, forming a rotor, which is rota tably mounted in bearings and so arranged than when in operation compression, combustion and expansion take place inside the rotor whilst the fluid is being rotated, whereby rotation of the rotor is effected and mechanical energy produced for an external use, the rotor consisting of a gas-tight inner wall, a gas-tight outer wall, a shaft, compressor blades, turbine blades, a number of partitions between the inner wall and outer wall to form the aforesaid lateral passages, conduit to channel the fuel to one or more nozzles, an ignition device and one or more combustion chambers, an inlet which is open to the atmosphere being provided in the outer wall near the axis of rotation on the compressor side of the rotor, and an outlet which is open to the atmosphere being provided in the outer wall also near the axis of rotation but on the expansion side of the rotor, the compressor blades fixed to the inner and outer wall on the inlet side of the rotor, at some distance from the axis of rotation, form passages of converging section which extend radially or substantially radially towards the periphery, the lateral passages extend axially or substantilly axially near the periphery of the rotor from the compressor outlet to the turbine inlet, and the turbine blades, fixed to the inner wall and outer wall on the outlet side of the rotor, form passages of diverging section which extend inwardly from the periphery to points nearer to the axis of rotation than the compressor blades.

The gas turbine may be so constructed that when it is in operation, the proportion of the rotor's radius in which the working fluid is compressed by the compressor blades in ratio to the greater proportion of the rotor's radius in which the working fluid is expanded is such that, at the optimum speed of rotation and at the optimum temperatures of the working fluid in the passages of the turbine, the velocity of the working fluid in passing through the rotor at no point exceeds the rotational velocity of the turbine blades, or preferably, the ratio may be such that the working fluid in passing through the rotor has at all points a negligible kinetic energy.

These characteristics clearly indicate the manner in which the working cycle is different from that of similar existing gas turbines and it is this aspect of the invention which substantially constitutes the improvement in efficiency.

But in order that frictional losses may be reduced, a stationary casing may be fixed around the outer wall of the rotor, which labyrinth glands or similar sealing devices between the casing and outer wall near to the inlet and outlet openings, and means (not shown) provided for maintaining a vacuum or partial vacuum in the space between the rotor and the stationary casing.

The minimise the stress on the metal of the rotor at the periphery by centrifugal force, a vacuum may be maintained in the area enclosed by the inner wall.

The gas turbine may be started by injecting fuel into the conduit, electrically igniting the fuel/air mixture in the combustion chamber or chambers and, unit independent operation of the turbine commences, by providing means (not shown) for rotating the rotor and supplying compressed air to the compressor inlet.

In order that the invention may be more readily understood, it will now be described with reference to the attached diagramatic drawings, in which: Figure 1 is a sectional view of the present invention in which a stationary casing is incorporated.

Figure 2 represents a view of the compressor side of the assembly but with the stationary casing and the outer wall of the rotor cut away.

Figure 3 represents a view of the turbine side of the assembly but with the stationary casing and outer wall of the rotor cut away.

In the drawings, the gas turbine comprises a rotor which is rotatably mounted in bearings 1, the rotor consisting of a gas-tight inner wall 2, a gas-tight outer wall 3, compressor blades 4, which are fixed to the inner wall and outer wall at some distance from the axis of rotation, forming a centrifugal compressor, turbine blades 5, which are also fixed to the inner and outer walls, extending from the periphery to points nearer to the axis of rotation than the compressor blades, forming a radial inward-flow turbine, and a number of partitions 6, similarly fixed to the inner and outer walls to form passages which are parallel to the axis of rotation and through which the working fluid passes from the compressor outlet to the turbine inlet, the compressor, tubine and passages being fixed together and to a shaft 7, a fuel conduit 8 is shown within the shaft and extending to a position near the periphery of the rotor where fuel may be mixed with air and ignited in one or a number of combustion chambers (not shown). When in operation, air is drawn through an opening - in the outer wall, compressed in the passages of the compressor, mixed with fuel and burnt in the passages which extend from the compressor outlet to the turbine inlet, expanded in the passages of the turbine, and finally expelled through another opening 10 in the outer wall. Also shown in the drawings is a stationary casing 1 1 fixed around the outer wall of the rotor, having labyrinth glands or similar sealing devices 1 2 near the inlet and outlet openings if it is desired to maintain a vacuum or partial vacuum in the space between the casing and the rotor.

Claims

1. A gas turbine comprising a centrifugal compressor, a radial inward-flow turbine, lateral passages through which the working fluid passes from the compressor outlet to the turbine inlet and means for injecting, igniting and burning a fuel in one or more of the said passages at constant pressure, the whole assembly being fixed together, forming a rotor, which is rotatably mounted in bearings and so arranged that when in operation compression, combustion and expansion take place inside the rotor whilst the fluid is being rotated, whereby rotation of the rotor is effected and mechanical energy produced for an external use, the rotor consisting of a gas-tight inner wall, a gas-tight outer wall, a shaft, compressor blades, turbine blades, a number of partitions between the inner and outer wall to form the aforesaid lateral passages, conduit to channel the fuel to one or more nozzles, an ignition device and one or more combustion chambers, an inlet which is open to the atmosphere being provided in the outer wall near the axis of rotation on the compressor side of the rotor, and an outlet which is open to the atmosphere being provided in the outer wall also near the axis of rotation but on the expansion side of the rotor, the compressor blades fixed to the inner and outer wall on the inlet side of the rotor, at some distance from the axis of rotation, form passages of converging section which extend radially or substantially radially towards the periphery, the lateral passages extend axially or substantially axially near the periphery of the rotor from the compressor outlet to the turbine inlet, and the turbine blades, fixed to the inner wall and outer wall on the outlet side of the rotor, form passages of diverging section which extend inwardly from the periphery to points nearer to the axis of rotation than the compressor blades.

2. A gas turbine as in Claim 1, in which when it is in operation, the proportion of the rotor's radius in which the working fluid is compressed by the compressor blades in ratio to the greater proportion of the rotor's radius in which the working fluid is expanded is such that, at the optimum speed of rotation and at the optimum temperatures of the working fluid in the passages of the turbine, the velocity of the working fluid in passing through the rotor at no point exceeds the rotational velocity of the turbine blades.

3. A gas turbine as in Claim 1, in which it is in operation, the proportion of the rotor's radius in which the working fluid is compressed by the compressor blades in ratio to the greater proportion of the rotor's radius in which the working fluid is expanded is such that, at the optimum speed of rotation and at the optimum temperatures of the working fluid in the passages of the turbine, the working fluid in passing through the rotor has at all points a negligible kinetic energy.

4. A gas turbine as in any preceding claim, in which a stationary casing is fixed around the outer wall of the rotor, with labyrinth glands or similar sealing devices between the casing and the outer wall, near to the inlet and outlet openings, and means provided for maintaining a vacuum or partial vacuum in the space between the rotor and the stationary casing.

5. A gas turbine as in any preceding claim, in which the area enclosed by the inner wall is a vacuum or a partial vacuum.

6. A gas turbine substantially as described and as shown in the drawings.