US2557131A - Gas turbine and cycle - Google Patents

Description

June ,1 v c. H. MILLER 2,557,131

GAS TURBINE Am) CYiCLE Filed F53. 2Q, 1948 2 Sheets-Sheet 1 (III/II I l I gvwembo o CHARLES H. MILLER,

J June 19, 1951 Fild eb; 20, 1948 vc. H. MILLER GAS TURBINE AND CYCLE 2 Sheets-Sheet 2 DIRECT'ON 0F RDTA cwanze's H. MILLER), 1

v 3,; v I D Patented June 19, 1951 UNITED STATES PATENT OFFICE GAS TURBINE AND CYCLE Charles H. Miller, Halifax, Nova Scotia, Canada Application February 20, 1948, Serial No. 9,653

3 Claims. (Cl. 60-41) This invention relates to gas turbines and to gas turbine cycles of operation.

An object of the invention is to provide a turbine in which a much higher temperature of the gases at the turbine is possible, due to means for cooling the turbine blading internally by a fresh charge of air, with consequent increase of thermal efliciency.

Another object of the invention is to provide a turbine having a separate regenerator, thus adding to the thermal efficiency of the unit.

A further object of the invention is to provide a turbine in which the turbine blading itself acts as a regenerator, the heat from the gases passing through the turbine being absorbed by the incoming fresh air charge.

Still another object of the invention is to provide a turbine in which all the air compressed is used to oxidize the fuel, thus reducing the required size of the compressor and in which the necessary power drawn from the turbine to drive the compressor is correspondingly reduced.

Other objects and advantages of the invention will become apparent from the following description of a preferred embodiment thereof, as illustrated in the accompanying drawings, and in which:

Figure 1 is an end elevation of a turbine according to the invention.

Figure 2 is a sectional elevation of the turbine shown in Figure 1.

Figure 3 is a sectional elevation of a. modified form of the turbine, showing a double entry, axial flow compressor and multiple stage turbine, and

Figure 4 is a transverse sectional plan view taken on line 44 of Figure 2.

In order to understand clearly the nature of the invention and the best means for carrying it out, reference may now be had to the drawings, in which like numerals denote similar parts throughout the several views.

As shown, there is a housing I seen in section in Figure 2, and having a turbine rotor l2 journalled in a bearing I3 supported by radial spider extensions I5 at one end, and also joumalled in right end bearing l4 in the housing, the rotor having a hub I6 extending to the left through the air inlet passageway l8 of the housing and being rotatable therein. The turbine thus provided may be of either the reaction or impulse type.

The rotor hub is progressively convergent in longitudinal section as seen in Figure 2, as it extends to the left through the air passageway l8, thus progressively reducing the space between the hub I6 and the interior wall surface of the casing, from left to right, resulting in increased velocity of the incoming air as it passed from location 20 to location 22. To the right of location 22, it will be observed that the radial thickness of the rotor hub increases precipitously, to form the radial web 24 of the rotor at the outer margin of which are located the rotor blades 26.

Each rotor blade thus has an air duct 28 extending therethrough, for conducting the incoming fresh air, in the direction of the arrow 30 in Figure 2 and thence into the combustion chamber 32 through duct 34 Inasmuch as the rotor blades are heated, as will be described below, the incoming fresh air is thus preheated before reaching the combustion chamber. The air may also be passed through a centrifugal compressor after entering the housing ID if desired, to further increase its velocity.

The conduit 34 is larger in diameter than the prior cross section of the path of the incoming air, thus acting as a diffuser, and the excess velocity of the air is converted into pressure, whereupon it flows into the combustion chamber 32 and supports the combustion of the fuel at constant pressure, the fuel being introduced into the chamber 32 through a pipe 36. Suitable ignition means is provided to burn the mixture of fuel and air in the combustion chambers 32, the resultant mixture of hot gases being delivered into the conduit at 38.

The gas flow is then divided at location 40, one part going through duct 42 to the heat exchanger or regenerator 44, and thence out through exhaust conduit duct 46 to the jet, or to another turbine if shaft work is desired. The other part of the gas flow at location 40 flows through duct portion 48 and in the direction of the arrow 50 to the turbine, first passing between the stationary guide vanes 52 and then between the rotor blades 26, and causing the further. rotation of the rotor. In other words, the heat energy of the gases is given up as they pass through the turbine, and is converted into mechanical shaft energy which turns the turbine l6, thus maintaining the cycle in operation.

The depressurized gases then mingle with the fresh charge of air as they both pass through the duct 34, and return to the combustion chamber 32, where the new mixture burns with the fuel. Thus the high velocity air-gas mixture at location 54 is diffused in the divergent duct 34, decreasing its velocity and increasing its pressure. The burned gases in the combustion cham ber and in duct 38 are hence at a higher pressure than those at location 54. The turbine blades 26 can be so designed that they simultaneously produce a reactive force, tending to rotate the turbine wheel, and change the pressure at 48 into a relative velocity corresponding to that of the air entering at 30. The design of the turbine thus fits in perfectly with the general design of the engine. The ejection of the air through the turbine blades also provides a reactive action by itself, which helps to rotate the turbine-compressor assembly.

Another advantage is that whereas in prior art engines, the turbine and compressor are mounted on opposite ends of a fairly long shaft, the present design, as described, has its shafting problems reduced since only one high speed unit is supported at both ends, these being fairly close together. And a reheating cycle is approached as some of the burned gases, which may yet contain unused air, is recirculated.

As shown in Figure 1, there are a number of sets of combustion chambers with their related ducts and regenerators, these being distributed angularly about the engine housing. Figure 3 shows a modified form of the invention, in which fresh air is not only drawn in from the left end of the housing, as already described, but is also down in from the right hand end, a duplicate housing extension being provided at 60, with a duplicate rotor 2, both rotors being journalled in a central hearing at 64 and in end bearing 6| and 63, and providing an air inlet at 66 and air passageway between the right hand rotor and the housing extension 60 in the same manner as for the left hand end as previously described. The incoming air passes in the direction of the arrow 68 through the hollow rotor blades 10 and ou to the right into the passageway 54 and through the duct 34, being mixed with the hot gases which have flowed through the duct 48 and through the rotor blades 26 which in turn were mingled with the incoming fresh air from the left hand air inlet 3.

Although I have described a prefered embodiment of my invention in specific terms, it is to be size, shape, materials and arangement without departing from the spirit and scope of the invention as claimed.

I claim:

1. A gas turbine comprising an elongated. hollow housing having a portion of substantially uniform internal diameter open at one end and a portion of greatly increased internal diameter at the opposite end of said first mentioned portion, a rotor hub extending through and journalled in said housing, said hub being of gradually increasing diameter in a direction away from the open end of said housing and having a portion of greatly increased diameter rotatable in the enlarged end portion of said housing, a set of hollow rotor blades peripherally mounted on the enlarged portion of said hub and so arranged that inlet air fiowing between said housing and said hub flows through said rotor blades, said housing providing an annular inlet chamber at one side of said set of rotor blades and at the opposite side of said set of rotor blades an annular exhaust chamber into which the inlet air flowing through said blades discharges, means providing adjacent said housing a combustion chamber having an inlet and an outlet end, a first conduit connecting the exhaust chamber in said housing to the inlet end of said combustion chamber, an exhaust conduit leading from the outlet end of the combustion chamber, a regenerator in said exhaust conduit and a second conduit connected to the exhaust conduit ahead of the regenerator and to the inlet chamber in said housing for recirculating a portion of the combustion gases through the housing for admixing with the inlet air.

2. A gas turbine comprising a hollow elongated housing having an open end, a rotor hub extending through and journalled in said housing. a set of hollow rotor blades on said hub at a location spaced from the open end of said housing, said housing providing an annular inlet chamber at one side and an annular exhaust chamber at the opposite side of said set of rotor blades and said rotor blades being effective to pass air therethrough from the interior of said housing into said exhaust chamber, means providing adjacent said housing a combustion chamber having an inlet end and an outlet end, a first conduit connecting the exhaust chamber in the housing to the inlet end of the combustion chamber, an exhaust conduit extending from the outlet end of the combustion chamber, a regenerator in said exhaust conduit, adapted to be communicated with a discharge duct, a second conduit connected to the exhaust conduit ahead of the regenerator and communicating with the inlet chamber in the housing for the passage of a portion of the combustion gases into the chamber for admixing with the inlet air in recirculation through the combustion chamber.

3. A gas turbine comprising a hollow, elongated housing having an open end, a rotor hub extending through and journalled in said housing, a set of hollow rotor blades on said hub at a location spaced from the open end of said housing, said housing providing an annular inlet chamber at one side and an annular exhaust chamber at the opposite side of said set of rotor blades and said rotor blades being effective to pass air therethrough from the interior of said housing into said exhaust chamber, means providing adjacent said housing a plurality of combustion chambers each having an inlet end and an outlet end, respective conduits connecting the exhaust chamber in said housing to the inlet ends of the combustion chamber, respective exhaust conduits connected to the outlet ends of said combustion chambers, a regenerator in each exhaust conduit adapted to be communicated with a discharge duct, and respective conduits connected to the exhaust conduits ahead of the regenerators and connected to the inlet chamber in the housing for the passage of a portion of the combustion gases into the inlet chamber in the housing for recirculation.

CHARLES H. MILLER.

Youngash Mar. 5, 1946 Clark July 16, 1946 FOREIGN PATENTS Country Date Great Britain Sept. 9, 1937 Number Number

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