GB2069065A - Ceramic gas turbine rotor - Google Patents
Ceramic gas turbine rotor Download PDFInfo
- Publication number
- GB2069065A GB2069065A GB8103330A GB8103330A GB2069065A GB 2069065 A GB2069065 A GB 2069065A GB 8103330 A GB8103330 A GB 8103330A GB 8103330 A GB8103330 A GB 8103330A GB 2069065 A GB2069065 A GB 2069065A
- Authority
- GB
- United Kingdom
- Prior art keywords
- ceramic
- turbine rotor
- rotor
- gas turbine
- hub
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 239000000919 ceramic Substances 0.000 title claims abstract description 41
- 239000002131 composite material Substances 0.000 claims abstract description 7
- 230000006835 compression Effects 0.000 claims abstract description 6
- 238000007906 compression Methods 0.000 claims abstract description 6
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 5
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims description 5
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims description 3
- 229910010271 silicon carbide Inorganic materials 0.000 claims description 3
- 239000007789 gas Substances 0.000 description 18
- 229910000601 superalloy Inorganic materials 0.000 description 5
- 229920000642 polymer Polymers 0.000 description 3
- 206010037660 Pyrexia Diseases 0.000 description 2
- 229910010293 ceramic material Inorganic materials 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 230000006378 damage Effects 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 1
- 239000000567 combustion gas Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000007847 structural defect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/30—Fixing blades to rotors; Blade roots ; Blade spacers
- F01D5/3084—Fixing blades to rotors; Blade roots ; Blade spacers the blades being made of ceramics
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D21/00—Shutting-down of machines or engines, e.g. in emergency; Regulating, controlling, or safety means not otherwise provided for
- F01D21/04—Shutting-down of machines or engines, e.g. in emergency; Regulating, controlling, or safety means not otherwise provided for responsive to undesired position of rotor relative to stator or to breaking-off of a part of the rotor, e.g. indicating such position
- F01D21/045—Shutting-down of machines or engines, e.g. in emergency; Regulating, controlling, or safety means not otherwise provided for responsive to undesired position of rotor relative to stator or to breaking-off of a part of the rotor, e.g. indicating such position special arrangements in stators or in rotors dealing with breaking-off of part of rotor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/28—Selecting particular materials; Particular measures relating thereto; Measures against erosion or corrosion
- F01D5/284—Selection of ceramic materials
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
- F02C3/00—Gas-turbine plants characterised by the use of combustion products as the working fluid
- F02C3/04—Gas-turbine plants characterised by the use of combustion products as the working fluid having a turbine driving a compressor
- F02C3/06—Gas-turbine plants characterised by the use of combustion products as the working fluid having a turbine driving a compressor the compressor comprising only axial stages
- F02C3/073—Gas-turbine plants characterised by the use of combustion products as the working fluid having a turbine driving a compressor the compressor comprising only axial stages the compressor and turbine stages being concentric
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Combustion & Propulsion (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Abstract
The rotor comprises a ceramic wheel 14 having an inner row of turbine blades 16 and an outer row of compressor blades 18 separated by a mid-blade shroud 20, and an outer shroud 22 filament wound with a composite so as to form a hoop 24 providing compression loading of the ceramic components during rotation. The wheel 14 has a ceramic or metallic hub 12 for attachment to a shaft. <IMAGE>
Description
SPECIFICATION
Ceramic gas turbine rotor
Background of the Invention
1. Field of the Invention
This invention pertains to the field of hightemperature, high-strength ceramics and more particularly to high-temperature, light-weight, high-strength ceramic gas turbine rotors.
2. Description ofPriorArt Efficiency ratings of power systems has become one of the most important design criteria in developing today's power systems. Studies have clearly indicated that the efficiency ratings of gas turbines can be greatly enhanced by permitting the combustion products to impinge on a turbine wheel at maximum temperatures.
However, combustion gases required to obtain the maximum efficiency for gas turbines are in the range of about 25000F which is greatly in excess of the operating temperature limits of state-of-theart superalloys. It was determined that if the superalloys were to be used not only would there be a weight problem, but complex cooling systems would have to be incorporated into the system.
This cooling would permit the use of these superalloys; however, the lower temperature would result in a decrease in the overall efficiency of the system.
It appeared that a more practical solution to the temperature/efficiency problem would be the use of high-temperature ceramics. However, unlike superalloys, ceramics are extremely brittle and this inherent problem has, to date, made them almost impossible to use in high-stress situations.
Because ceramic materials exhibit only moderate strengths in tension and are extemely flawsensitive when used in that fashion, for example, as a rotor vane on a rotating turbine wheel, any structural defect will result in destruction of the ceramic rotor vane as well as ultimate destruction of the turbine rotor. In sharp contrast to the low tensile strength, the compressive strength of ceramics is in the range of ten times that which the ceramic will exhibit when put under tensile stress. Therefore, it would appear desirable to maintain the ceramic components of a turbine rotor in compression rather than in tension during the life cycle of the turbine.
Summary of the Invention
Accordingly, there is provided by the present invention an axial ceramic gas turbine rotor which comprises a ceramic or metal hub attached to a ceramic wheel section containing an inner row of power turbine airfoils and an exterior row of air compressor blades separated from each other by a mid-vane shroud. The air compressor blades also have an exterior shroud. The outer rim of the assembly is filament wound with a high strengthto-weight ratio composite structure consisting of a high modulus filament impregnated with a hightemperature polymer.
Objects of the Invention
Therefore, it is an object of the present
invention to provide a ceramic gas turbine rotor
capable of maintaining all ceramic components in
compression during operation.
Another object of the present invention is to
provide a high-temperature gas turbine rotor.
Yet a further object of the present invention is to provide a light-weight ceramic gas turbine
rotor.
Still a further object of the present invention is to provide a high-strength ceramic gas turbine
rotor.
Other objects, advantages and novel features of
the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the
accompanying drawings.
Brief Description of the Drawings
Fig. 1 is a perspective view of the ceramic gas turbine rotor.
Fig. 2a is a plan view af the ceramic gas turbine rotor.
Fig. 2b is a segmented cross-section taken along line A-A of Fig. 2a.
Fig. 3 is a perspective view of an element of the ceramic gas turbine rotor.
Fig. 4 is a schematic representation of a gas turbine cycle.
Description of the Preferred Embodiments
Referring now to Figs. 1 through 2b, there is shown an axial ceramic gas turbine rotor generally designated as 10 of silicon nitride, silicon carbide, sialon, or similar high-strength ceramic. The gas turbine rotor 10 is envisioned to comprise a ceramic or metal hub 12 attached to a ceramic wheel 14. The wheel 14 further comprises an inner row of power turbine airfoils 1 6 and an exterior row of. air compressor blades 18 separated from each other by a mid-vane shroud 20. The air compressor blades 18 also have an exterior shroud 22. The outer time 23 of the exterior shroud 22 is filament wound with a high strengthto-weight ratio composite structure, wherein the structure comprises a high modulus filament impregnated with a high-temperature polymer.
The filament wound composite structure forms a hoop 24 against which the ceramic components are loaded in compression during rotation of the rotor assembly. It is essential to this concept that the cold air compressor blades 1 8 be exterior to the hot power turbine airfoil 1 6 section because the air compressor section not only acts as one stage of the air compressor in a gas turbine engine cycle, but together with the incoming air acts as the thermal barrier protecting the filament wound hoop 24 structure from the high temperatures of the power section of the rotor.
Filament wound composite structures, which utilize organic chemical polymers as matrix, have a maximum use temperature of approximately 6000F. Leakage from the power turbine section through the seal at the mid-vane shroud 20 will not cause failure of the rotor 10, but will only result in slightly increased temperatures of the incoming air to the burner assembly.
Structural ceramic materials such as silicon nitride are required to utilize high turbine inlet temperatures such as 25000F which are required to increase efficiencies of gas turbine engines. An extremely low coefficient of thermal expansion, together with high strength such as exhibited by silicon nitride, are also essential properties of the rotor material because of the high thermal gradients inherent in this design.
The rotor assembly can be fabricated as a monolithic ceramic rotor 10, Fig. 1 , which is filament wound with the appropriate composite structure and attached through a hub 12 to the shaft 26 or it can be assembled from ceramic pie sections shown in Fig. 3. The individual pieshaped segments are assembled into a wheel and the outer shroud filament wrapped. The center section will be held in compression and attached to the shaft 26 by a hub 12 assembly, as illustrated in Fig. 2b. The ability to construct this unique rotor assembly from individual components, as conceived in Fig. 3, will allow larger ceramic rotors 10 to be fabricated than can be fabricated as a monolithic piece by the present state of ceramic technology. In addition, the smaller component piece by the present state of ceramic technology.In addition, the smaller component parts can be fabricated and tested more economically and at less risk than a larger monolithic component.
In addition to high temperature capability, the rotor discussed herein is extremely light-weight.
Silicon nitride, silicon carbide, sialon, etc., have a density of approximately 3.0 to 3.8 grams/Cc compared to density of approximately 8 grams/Cc for a conventional superalloy.
A representative gas turbine cycle showing possible arrangement of key components is illustrated in Fig. 4.
Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that, within the scope of the appended claims, the - invention may be practiced otherwise than as specifically described.
What is claimed and desired to be secured by
Letters Patent of the United States is:
Claims (4)
1. A ceramic turbine rotor, comprises:
a hub for cdnnecting said rotor to a shaft;
a ceramic wheel comprises:
an inner row of power turbine airfoils;
an outer row of compressor blades;
a mid-vane shroud disposed so as to isolate said airfoils from said compressor blades; and
an outer shroud circumferentially disposed so as to prevent gas from escaping to the exterior of said turbine rotor; and
a filament wound composite hoop circumferentially disposed about said outer shroud so as to provide a means for compression loading the ceramic components during rotation.
2. The ceramic turbine rotor of Claim 1 wherein said hub is metallic.
3. The ceramic turbine rotor of Claim 1 wherein said hub is ceramic.
4. The ceramic turbine rotor of Claim 1 wherein said ceramic is selected from the group consisting of silicon nitride, silicon carbide, and sialon.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US11829580A | 1980-02-04 | 1980-02-04 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB2069065A true GB2069065A (en) | 1981-08-19 |
Family
ID=22377719
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8103330A Withdrawn GB2069065A (en) | 1980-02-04 | 1981-02-03 | Ceramic gas turbine rotor |
Country Status (7)
| Country | Link |
|---|---|
| JP (1) | JPS56124603A (en) |
| DE (1) | DE3103821C2 (en) |
| ES (1) | ES498630A0 (en) |
| FR (1) | FR2475113A1 (en) |
| GB (1) | GB2069065A (en) |
| IT (1) | IT1142247B (en) |
| SE (1) | SE8100355L (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2164098A (en) * | 1984-09-07 | 1986-03-12 | Rolls Royce | Improvements in or relating to aerofoil section members for turbine engines |
| US4580943A (en) * | 1980-12-29 | 1986-04-08 | The United States Of America As Represented By The Secretary Of The Army | Turbine wheel for hot gas turbine engine |
| FR2613772A1 (en) * | 1987-04-13 | 1988-10-14 | Gros Jean Marc | Integral compressor and turbine wheel. Integral diffuser and distributor. Integral air inlet and exhaust nozzle |
| DE102009012749A1 (en) * | 2009-03-12 | 2010-09-23 | Siemens Aktiengesellschaft | Turbine stage element for turbine, has through flow opening for fluid stream and predetermined aerodynamic profile along through flow opening, where turbine stage element has fiber-reinforced material |
| WO2013040679A1 (en) * | 2011-09-23 | 2013-03-28 | Socpra Sciences Et Génie S.E.C. | Rotor assembly having a concentric arrangement of a turbine portion, a cooling channel and a reinforcement wall |
| FR3005690A1 (en) * | 2013-05-16 | 2014-11-21 | Gerard Cerdan | COMPRESSOR TURBOREACTOR AND MONOBLOCS TURBINE (TR A CTM) |
| EP2189624A3 (en) * | 2008-11-24 | 2017-05-31 | General Electric Company | Fiber composite reinforced aircraft gas turbine engine drums with radially inwardly extending blades |
| GB2554477A (en) * | 2016-09-23 | 2018-04-04 | Intelligent Power Generation Ltd | An axial turbine |
| WO2018094536A1 (en) * | 2016-11-25 | 2018-05-31 | Societe de Commercialisation des Produits de la Recherche Appliquée Socpra Sciences et Génie S.E.C. | High temperature ceramic rotary turbomachinery |
| US11208893B2 (en) | 2015-05-25 | 2021-12-28 | Socpra Sciences Et Genie S.E.C. | High temperature ceramic rotary turbomachinery |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2161110B (en) * | 1984-07-07 | 1988-03-23 | Rolls Royce | An annular bladed member having an integral shroud and a method of manufacture thereof |
| DE3508889C1 (en) * | 1985-03-13 | 1992-02-20 | Alpine Ag, 8900 Augsburg | Air classifier with wear-free classifying wheel |
| FR2951226B1 (en) * | 2009-10-14 | 2013-01-04 | Turbomeca | AIR FILTERING DEVICE INTO INTERNAL COMBUSTION ENGINE INPUT WITH VENTILATION MEANS |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3042366A (en) * | 1958-05-05 | 1962-07-03 | Holmquist Ernst Rudolf Magnus | Axial flow gas turbine |
| US3635577A (en) * | 1968-04-11 | 1972-01-18 | Aerostatic Ltd | Coaxial unit |
| DE2027861C3 (en) * | 1970-06-06 | 1973-12-06 | Motoren- Und Turbinen-Union Muenchen Gmbh, 8000 Muenchen | Disc-shaped impeller for high-speed axial turbines |
| IT975329B (en) * | 1972-10-23 | 1974-07-20 | Fiat Spa | STRUCTURE OF STATIC OR ROTATING METALLIC AND NOM METALLIC PARTS FOR HIGH TEMPERATURE ENVIRONMENTS ESPECIALLY FOR ROTORS AND STATE OF GAS TURBINES |
| SE375583B (en) * | 1973-05-22 | 1975-04-21 | United Turbine Ab & Co | |
| US4017209A (en) * | 1975-12-15 | 1977-04-12 | United Technologies Corporation | Turbine rotor construction |
-
1981
- 1981-01-16 FR FR8100789A patent/FR2475113A1/en active Granted
- 1981-01-19 ES ES498630A patent/ES498630A0/en active Granted
- 1981-01-22 SE SE8100355A patent/SE8100355L/en not_active Application Discontinuation
- 1981-01-28 IT IT47655/81A patent/IT1142247B/en active
- 1981-02-03 GB GB8103330A patent/GB2069065A/en not_active Withdrawn
- 1981-02-04 DE DE3103821A patent/DE3103821C2/en not_active Expired
- 1981-02-04 JP JP1449281A patent/JPS56124603A/en active Pending
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4580943A (en) * | 1980-12-29 | 1986-04-08 | The United States Of America As Represented By The Secretary Of The Army | Turbine wheel for hot gas turbine engine |
| GB2164098A (en) * | 1984-09-07 | 1986-03-12 | Rolls Royce | Improvements in or relating to aerofoil section members for turbine engines |
| FR2613772A1 (en) * | 1987-04-13 | 1988-10-14 | Gros Jean Marc | Integral compressor and turbine wheel. Integral diffuser and distributor. Integral air inlet and exhaust nozzle |
| EP2189624A3 (en) * | 2008-11-24 | 2017-05-31 | General Electric Company | Fiber composite reinforced aircraft gas turbine engine drums with radially inwardly extending blades |
| DE102009012749A1 (en) * | 2009-03-12 | 2010-09-23 | Siemens Aktiengesellschaft | Turbine stage element for turbine, has through flow opening for fluid stream and predetermined aerodynamic profile along through flow opening, where turbine stage element has fiber-reinforced material |
| DE102009012749B4 (en) * | 2009-03-12 | 2012-08-30 | Siemens Aktiengesellschaft | Power amplifier with fiber composite |
| EP2744993A4 (en) * | 2011-09-23 | 2015-05-20 | Socpra Sciences Et Génie S E C | Rotor assembly having a concentric arrangement of a turbine portion, a cooling channel and a reinforcement wall |
| CN103975141A (en) * | 2011-09-23 | 2014-08-06 | 索克普拉科学与工程公司 | Rotor assembly having a concentric arrangement of a turbine portion, a cooling channel and a reinforcement wall |
| WO2013040679A1 (en) * | 2011-09-23 | 2013-03-28 | Socpra Sciences Et Génie S.E.C. | Rotor assembly having a concentric arrangement of a turbine portion, a cooling channel and a reinforcement wall |
| US9670840B2 (en) | 2011-09-23 | 2017-06-06 | Socpra—Science Et Genie, S.E.C. | Rotor assembly having a concentric arrangement of a turbine portion, a cooling channel and a reinforcement wall |
| FR3005690A1 (en) * | 2013-05-16 | 2014-11-21 | Gerard Cerdan | COMPRESSOR TURBOREACTOR AND MONOBLOCS TURBINE (TR A CTM) |
| US11208893B2 (en) | 2015-05-25 | 2021-12-28 | Socpra Sciences Et Genie S.E.C. | High temperature ceramic rotary turbomachinery |
| GB2554477A (en) * | 2016-09-23 | 2018-04-04 | Intelligent Power Generation Ltd | An axial turbine |
| GB2554490A (en) * | 2016-09-23 | 2018-04-04 | Intelligent Power Generation Ltd | An axial turbine |
| GB2554490B (en) * | 2016-09-23 | 2019-02-20 | Intelligent Power Generation Ltd | An axial turbine |
| WO2018094536A1 (en) * | 2016-11-25 | 2018-05-31 | Societe de Commercialisation des Produits de la Recherche Appliquée Socpra Sciences et Génie S.E.C. | High temperature ceramic rotary turbomachinery |
| EP3545173A4 (en) * | 2016-11-25 | 2020-07-29 | Societé de Commercialisation des Produits de la Recherche Appliquée SOCPRA Sciences et Génie S.E.C | High temperature ceramic rotary turbomachinery |
Also Published As
| Publication number | Publication date |
|---|---|
| IT1142247B (en) | 1986-10-08 |
| IT8147655A0 (en) | 1981-01-28 |
| SE8100355L (en) | 1981-08-05 |
| FR2475113B1 (en) | 1985-03-22 |
| ES8204058A1 (en) | 1982-04-01 |
| JPS56124603A (en) | 1981-09-30 |
| FR2475113A1 (en) | 1981-08-07 |
| ES498630A0 (en) | 1982-04-01 |
| DE3103821A1 (en) | 1981-12-03 |
| DE3103821C2 (en) | 1985-04-04 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |