US3919845A

US3919845A - Dual fluid single rotor turbine

Info

Publication number: US3919845A
Application number: US411919A
Authority: US
Inventors: Michael Eskeli
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-10-30
Filing date: 1973-11-01
Publication date: 1975-11-18
Anticipated expiration: 1992-11-18

Abstract

A method and apparatus for generating power in a rotating turbine wheel, wherein two working fluids are circulated within a rotating turbine rotor with a third fluid providing a supply of heat, and also serving as a heat sink. Said two working fluids are compressed and are in heat exchange relationship during and after compression; after compression, said working fluids are expanded. Work is required by said fluids during said compression and acceleration, and work is obtained from said fluids during said expansion and deceleration. Typical fluids for use are carbon dioxide as one of the working fluids releasing heat during said compression and receiving heat from said heating fluid, and nitrogen as the other working fluid receiving heat during said compression and being cooled by releasing heat to said heat sink. Said heating fluid may be water. Alternately, a separate heating fluid, and a separate coolant may be used.

Description

United States Patent Eskeli DUAL FLUID SINGLE ROTOR TURBINE Michael Eskeli, 6220 Orchid Lane, Dallas, Tex. 75230 Filed: Nov. 1, 1973 Appl. No.: 411,919

Related U.S. Application Data Continuation-impart of Ser. No. 410,985, Oct. 30, 1973, Pat. No. 3,861,147.

Inventor:

References Cited UNITED STATES PATENTS 10/1948 Roebuck 165/88 2,522,781 9/1950 Exner 62/499 2,529,765 11/1950 Exner 62/499 FOREIGN PATENTS OR APPLICATIONS 605,618 7/1948 United Kingdom 415/179 an O r 19 COO [ 51 Nov. 18,1975

Primary E.raminerAlbert W. Davis, Jr. Assistant Examiner-Sheldon Richter 1 1 ABSIRACT A method and apparatus for generating power in a rotating turbine wheel, wherein two working fluids are circulated within a rotating turbine rotor with a third fluid providing a supply of heat, and also serving as a heat sink. Said two working fluids are compressed and are in heat exchange relationship during and after compression; after compression, said working fluids are expanded. Work is required by said fluids during said compression and acceleration, and work is obtained from said fluids during said expansion and deceleration. Typical fluids for use are carbon dioxide as one of the working fluids releasing heat during said compression and receiving heat from said heating fluid, and nitrogen as the other working fluid receiving heat during said compression and being cooled by releasing heat to said heat sink. Said heating fluid may be water. Alternately, a separate heating fluid, and a separate coolant may be used.

1 Claim, 6 Drawing Figures DUAL FLUID SINGLE ROTOR TURBINE CROSS REFERENCES TO RELATED APPLICATIONS This application is a continuation-in-part application of Sealed Single Rotor Turbine, filed Oct. 30, I973, Ser. No. 410,985, now US. Pat. No. 3,861,147.

This invention relates generally to turbines for generating power wherein a working fluid is passed from higher energy level to lower energy level generating said power in a rotating rotor, with heat addition and cooling being provided within said rotor.

There have been various types of turbines previously; in some of these, a fluid is accelerated in a stationary nozzle and then passed to vanes mounted on a rotating rotor where the kineticenergy contained by said fluid after said acceleration is converted to power.

These conventional turbines require a pressurized fluid source for their operation, such as steam, thus making the entire power generating system costly.

FIG. 1 is a cross section of the turbine power generator, and

FIG. 2 is an end view of the unit shown in FIG. 1, with portions removed to show interior details; 7

FIG. 3 is a cross section of another form of the turbine, and FIG. 4 is an end view of the unit shown in FIG. 3, with portions removed to show interior details;

FIG. 5 is a pressure-enthalpy diagram with a work cycle illustrated thereon for the heat exchanger part of the turbine, and

FIG. 6 is a pressure-enthalpy diagram for power generating part of the turbine with a work cycle illustrated thereon.

It is an object of this invention to provide a power generating turbine wherein a heat exchanger portion is provided to elevate temperature of the available heat, and then pass this heat to a turbine to generate power; all this being combined within a single rotor. Further, it is an object of this invention to provide a turbine wherein the turbine rotor is constructed in such manner as to allow placement of said rotor within an evacuated casing thus reducing friction losses on said rotor. It is also an object of this invention to provide a power generating turbine wherein low temperature heat source may be used to generate power.

The turbine of this invention may have either three or four fluids being circulated within the rotor. In the following, the fluid being sealed within one portion of the rotor, and being the fluidgenerating the power, is the first fluid; the fluid being sealed within another portion of the rotor and being used to increase the temperature of the available heat, is the second fluid; the fluid providing the heating and which also may be used for cooling, is the third fluid; and the fluid being used exclusively for cooling, is the fourth fluid.

Functionally, the first fluid and the second fluid are compressed by centrifugal action by the rotor on the fluids with accompanying temperature increase for both fluids; also, these two fluids are in heat exchange relationship during this compression. Said first fluid and said second fluid are selected to provide for greater temperature increase for said second fluid, so that heat is transferred from said second fluid to said first fluid during and after compression of said first fluid. After such compression and heat removal, said second fluid is allowed to expand and during and after expansion heat is added to said second fluid from a lower temperature heat source, after which said second fluid is passed to be compressed thus completing the cycle. Said first fluid is allowed to expand after said heat addition, and during such expansion work is produced, with accompanying temperature and pressure decrease, and after such expansion, the first fluid is cooled by removing heat, after which said first fluid is passed to be compressed again thus completing the cycle. Part of the work generated by said first fluid is needed to rotate said rotor section for said second fluid, and the remainder is available to be passed out as the useful work output of the turbine.

Referring to FIG. 1, therein is shown a cross section of one form of the turbine. 10 is casing supporting bearings and

seals

19 and 29, and shaft 20. Said first fluid is compressed within rotor 11, with vanes 36 assuring that said first fluid will rotate with said rotor, and with heat being added to said first fluid from said second fluid through heat conductive wall 27 and with said vanes 36 also serving as heat exchange members. After compression, said first fluid is passed through nozzles 23 in forward direction thus providing for said first fluid an absolute tangential velocity that is greater than the tangential velocity of said nozzles, after which said first fluid will enter to the expansion side of said rotor with vanes 15 .assuring that said first fluid will rotate with said rotor and for receiving the work associated with deceleration of said first fluid. After expansion, the first fluid temperature is usually too high to permit passage of said first fluid to said compression side of the rotor, and thus a cooling heat exchanger 17 is provided to reduce the first fluid temperature to a predetermined value. After such cooling, said first fluid is passed to said compression side, for compression in the outward passages for said first fluid. 14 is a dividing wall. The second fluid is compressed in its outward extending passageways, with vanes 25 assuring that said second fluid will rotate with said rotor, and also serving as heat exchange members. Heat is removed from said second fluid during said compression, and after compression, said second fluid is passed through nozzles 12 in backward direction thus providing for said second fluid an absolute tangential velocity that is less than the tangential velocity of said nozzles 12. Said second fluid is then passed to space 34 and from there to inward extending second fluid passageways, where vanes 33 will assure that said second fluid will rotate with said rotor and also for receiving the work associated with deceleration of said second fluid. During said expansion and deceleration, heat is added to said second fluid to maintain its temperature at a predetermined value; this heat addition may also continue after said expansion. After said heat addition, said second fluid is passed to be compressed again, by vanes 25. The third fluid enters rotor 11 shaft 20 via opening 21, and is passed to heat exchanger 17, arranged to be in counterflow with said first fluid; after passing through said heat exchanger 17, said third fluid will pass along passage 22 to conduit 35 to heat exchanger 32, where said third fluid is in parallel flow with said second fluid; after that said third fluid In FIG. 2, an end view of the unit illustrated in FIG. 1, is shown, with portions removed to show interior details. is casing, 1 1 is rotor, 12 is second fluid nozzles, 33 is vanes, 34 is fluid space, 32 is heating heat exchanger, is shaft, 37 indicates direction of rotation for the rotor, 13 is fluid space, 36 are vanes, 23 are nozzles, 14 is divider, 15 are vanes. It should be noted that nozzles 12 are similar in cross section to nozzles 23.

In FIG. 3, another form of the turbine is shown. In this turbine, the outer rotor cavity contains said first fluid, and inner cavity contains said second fluid, with the function of both fluids being similar to that described hereinbefore for the unit shown in FIG. 1. 55 is casing, 54 is rotor, 52 and 66 are bearings and seals supporting

rotor shaft

50, 51 and 67 are entry and exit, respectively, for third fluid, 68 and 70 are entry and exit respectively, for fourth fluid, 69 is third fluid passage. First fluid leaves cooling heat exchanger 65 and is compressed with vanes 63 assuring that said first fluid will rotate with said rotor and heat being added through wall 73 and vanes 63 also serving as heat exchange members. After compression and heat addition, said first fluid passes through nozzles 62 oriented to discharge forward thus providing for said first fluid an absolute tangential velocity that is greater than the tangential velocity of said nozzles 62; after which said first fluid enters space 61 and then passes to the expansion side of said rotor to inward extending fluid passages with vanes 56 assuring that said first fluid will rotate with said rotor and for receiving the work associated with deceleration of said first fluid; after which said first fluid is passed to heat exchanger 65, and after cooling, passed to said outward extending passageways for said compression. Said second fluid is compressed with accompanying pressure and temperature increase by said rotor with vanes 60 assuring that said second fluid will rotate with said rotor; with heat being transferred to said first fluid during said compression and with vanes 60 also serving as heat exchange members; after said compression said second fluid is passed through nozzles 59 to expansion side of said rotor to space 58, and from there to inward extending passageways where vanes 72 will assure that said second fluid will rotate with said rotor and for receiving the work associated with said deceleration of said second fluid; during said expansion heat is added to said second fluid in heat exchanger 64, after which said second fluid is passed to said outwardly extending fluid passages for said compression. 67 is dividing wall, 68 is casing vent opening into which a vacuum pump may be connected, 57 is dividing wall.

In FIG. 4, an end view of the unit shown in FIG. 3 is illustrated, with portions removed to show interior details. 55 is casing, 56 are vanes, 57 is dividing wall, 62 are nozzles, 63 are vanes, 7 1 indicates direction of rotation for rotor, 50 is shaft, 63 are vanes and heat exchange members, 64 is heat exchanger for heating, 72 are vanes, 58 is fluid space, 59 are nozzles for second fluid, 56 are vanes, 54 is rotor.

In FIG. 5, a pressure-enthalpy diagram is shown with a work cycle illustrated thereon for said second fluid. 70 is pressure line and 71 is enthalpy line, 72 are constant enthalpy lines, 73 are constant pressure lines and 74 are constant entropy lines. Compression with heat removal is shown by line 75 to 77, and expansion at constant entropy is shown by line 77 to 76, and expansion with heat addition is shown by line 76 to 75, thus completing the cycle.

In FIG. 6, a typical pressure-enthalpy diagram is shown for said first fluid, with line 80 being pressure line, and line 81 being the enthalpy line. 82 is constant enthalpy, 83 is constant pressure and 84 is constant entropy. The first fluid is compressed from 85 to 86 with constant entropy, and then heat is added from 86 to 87, after which the fluid is expanded isentropically from 87 to 88 and then heat is removed from 88 to 85 thus completing the work cycle.

In operation, a suitable amount of first fluid is inclosed within its cavity in the rotor, and also a suitable amount of said second fluid is inclosed within its cavity within the rotor. The rotor is started by using a suitable starter, and brought to its operating speed. The circulation of the various fluids within the rotor passages is as described hereinbeforc. Heat is supplied to the turbine by said third fluid. Cooling for the first fluid is provided by said third or said fourth fluid. Said third and fourth fluids are supplied from external sources. Work is produced by said turbine, and said work is then passed to an external load.

The first fluid and the second fluid are selected to have different amounts of temperature increase, as noted hereinbeforc. Both fluids are usually gaseous. In some instances, it may be possible to operate said turbine by using as a first fluid and as a second fluid the same fluid at different initial pressures. As an example, said first fluid may be nitrogen, at 15 psia pressure at center during operation, and said second fluid may be carbon dioxide, at psia pressure at area nearest rotor center. The selection of these two fluids must be carefully made to have an operable unit, and the physical properties at the pressures and temperatures contemplated must be well known for the first and second fluids. Generally, said first fluid is selected to have best possible work output for the operating conditions; the said first fluid should be selected using tables for real gases, or by experimentation. Similarly, the second fluid is selected using tables for real gases or by experimentation, to have a gas with a greater temperature increase within rotor than for said first fluid, while at the same time having a low work input within said rotor during operation. The two fluids, carbon dioxide and nitrogen meet these conditions. Other fluids that may be used as said first fluid are air, oxygen, carbon monoxide, and others. For said second fluid, various hydrocarbons, halogenated hydrocarbons, nitrogen and other fluids may be used.

The said third fluid may be either a gas or a liquid. Normally, a liquid will be suitable, and water may be used.

The function of the power generating portion of the turbine is as follows: Said first fluid is accelerated and compressed with some temperature increase of its own, and additional increase in enthalpy and temperature is provided by the heat being transferred from said second fluid. This heat addition will increase the available energy level of said first fluid and decrease its density, so that pressure build-up on the expansion side due to centrifugal force is reduced, thus allowing for a larger radius for vanes 15, FIG. 1, while still providing sufficient pressure differential to maintain first fluid flow in the indicated direction. Thus, due to the greater initial tip velocity of the rotor vanes on the expansion side, more work is transferred to rotor via vanes 15, due to greater amount of deceleration, than is required to accelerate said first fluid in the compression side, where the first fluid density is greater. Thus, the circulation of said first fluid within said rotor cavity is due to density differentials created by additions and subtractions of heat, while the work input and output are due to amounts of acceleration and deceleration of said first fluid within said rotor; noting that part of the acceleration is done in nozzles where only a portion of the reaction is transferred to said nozzles and rotor, and the first fluid is free of restraints after said passage through said nozzles. Note the space free of vanes in each instance after the fluid leaves a set of nozzles.

Various controls and governors are used with the device of this invention. They do not form a part of this invention and are not further described herein.

Vanes l5 and vanes in FIG. 1, are normally radial; however, they may be made curved, if desired. Similarly,

vanes

56 and 60 in FIG. 3, are normally radial, but they may be made curved if desired. The rotors are made of heavy material section as shown, and the rotor walls are usually thicker near rotor center to provide for needed strength for high speed rotation. The

nozzles

59 and 12, are similar in construction to

nozzles

62 and 23. The heat exchanger are usually made from tubing and are spiral in form to provide needed flow patterns shown in figures. The rotor of FIG. 3 may have thermal insulation as required, similar to FIG. 1.

What is claimed is:

1. A power generator comprising:

a. a means for rotatably supporting a shaft;

b. a shaft;

c. a rotor supported by said shaft so as to rotate in unison therewith, said rotor having:

i. a turbine section comprising a first outward extending passageway and a first inward extending passageway for a first fluid with said outward extending first fluid passageway and said inward extending first fluid passageway being connected at their outward ends and at their inward ends for circulation of said first fluid, said outward extending first fluid passageway having a set of first nozzles for passing said first fluid, said first fluid passageways having a first heat exchanger means for adding heat into said first fluid and said first fluid passageways having a second heat exchanger means for removing heat from said first fluid;

a heat exchanger section comprising a second outward extending passageway and a second inward extending passageway for a second fluid with said outward extending second fluid passageway and said inward extending second fluid passageway being connected at their inward ends and their outward ends for circulation of said second fluid, said outer ends of said second outward extending second fluid passageways having nozzles at their outward ends for passing said second fluid into said inward extending second fluid passageways, said second fluid passageways being provided with a third heat exchanger means for adding heat into said second fluid, and said second fluid passageways being provided with a fourth heat exchanger means for transferring heat from said second fluid into said first heat exchanger means and from there into said firstfluid.

Claims

1. A power generator comprising: a. a means for rotatably supporting a shaft; b. a shaft; c. a rotor supported by said shaft so as to rotate in unison therewith, said rotor having: i. a turbine section comprising a first outward extending passageway and a first inward extending passageway for a first fluid with said outward extending first fluid passageway and said inward extending first fluid passageway being connected at their outward ends and at their inward ends for circulation of said first fluid, said outward extending first fluid passageway having a set of first nozzles for passing said first fluid, said first fluid passageways having a first heat exchanger means for adding heat into said first fluid and said first fluid passageways having a second heat exchanger means for removing heat from said first fluid; ii. a heat exchanger section comprising a second outward extending passageway and a second inward extending passageway for a second fluid with said outward extending second fluid passageway and said inward extending second fluid passageway being connected at their inward ends and their outward ends for circulation of said second fluid, said outer ends of said second outward extending second fluid passageways having nozzles at their outward ends for passing said second fluid into said inward extending second fluid passageways, said second fluid passageways being provided with a third heat exchanger means for adding heat into said second fluid, and said second fluid passageways being provided with a fourth heat exchanger means for transferring heat from said second fluid into said first heat exchanger means and from there into said first fluid.