Patent Application
20110126508
1. Field of the Invention
The invention relates to turbine engines.
2. Description of Related Prior Art
U.S. Pat. No. 6,612,217 discloses penetration resistant fabric structures and materials. A ballistic barrier is applied for protecting an aircraft from damage due to projectile penetration. The aircraft has a fuselage including an outer skin, an inner panel and a structure. The ballistic barrier disclosed in the '217 patent includes at least one layer of high strength fabric disposed between the outer skin and the inner panel of the aircraft. The fabric is substantially fixedly positioned with respect to the fuselage of the aircraft.
In summary, the invention is a fan. The fan includes a shaft rotatable about an axis. The fan also includes a blade engaged with the shaft for rotation about the axis. The fan also includes a case encircling the axis. The case is positioned radially outward of the blade and the shaft. The fan also includes a blanket mounted to the case. The case and the blanket are operable to cooperate with one another to prevent the blade from escaping the case upon the blade separating from the shaft. The blanket is at least partially impregnated with shear thickening fluid.
Advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
A plurality of different embodiments of the invention is shown in the Figures of the application. Similar features are shown in the various embodiments of the invention. Similar features have been numbered with a common reference numeral and have been differentiated by an alphabetic suffix. Also, to enhance consistency, the structures in any particular drawing share the same alphabetic suffix even if a particular feature is shown in less than all embodiments. Similar features are structured similarly, operate similarly, and/or have the same function unless otherwise indicated by the drawings or this specification. Furthermore, particular features of one embodiment can replace corresponding features in another embodiment or can supplement other embodiments unless otherwise indicated by the drawings or this specification.
The invention, as exemplified in the embodiment described below, can be applied to contain components liberated from a turbine engine. The '217 patent described above is concerned with protecting the interior of a fuselage of an aircraft. As a result, the '217 patent requires extensive amounts of fabric. The fabric is applied to the fuselage and it is not possible to always predict the trajectory of components liberated from a turbine engine. Excessive fabric is therefore required for the invention disclosed in the '217 patent to protect the interior of the fuselage from all possible trajectories. The present invention, on the other hand, recognizes that applying penetration resistant fabric around the rotating components requires less fabric.
Another shortcoming of the '217 patent is that it fails to contemplate the risk of components liberated from a turbine engine relative to personnel not in the fuselage of an aircraft. In aircraft applications for turbine engines, components may become liberated from a turbine engine while the aircraft is on the ground. Such components pose a danger to ground crew, mechanics, and passengers boarding the aircraft. Further, turbine engines are also applied in non-aircraft applications. Such turbine engines can be operated in working environments for humans. Thus, the present invention provides two substantial improvements over the prior art, including minimizing the use of penetration-resistant fabric and providing a greater scope of protection.
Referring to
A nose cone assembly 28 can be attached to the fan 14. A turbine case 30 can encircle the core engine components (the compressor, combustor and turbine sections 16, 18, 20). The turbine case 30 can be fixed to a non-rotating hub 32 through a plurality of struts 34. Downstream of the combustor section 18, a row of turbine vanes, such as vanes 36, 38 can be positioned to direct the flow of combustion gases to the turbine section 20. The vanes 36, 38 can extend radially relative to the centerline axis 24, between an outer case 40 and an inner case 42. The outer case 40 can be integral with or separately formed from the case 30.
In a second embodiment, a fan can be defined by the compressor section 16. A low-pressure (LP) compressor blade 50 can be engaged with an LP shaft 52 for rotation about the axis 24. The case 40 encircles the axis 24 and is positioned radially outward of the blade 50 and the LP shaft 52. A blanket 54 is mounted to the case 40. The case 40 and the blanket 54 are operable to cooperate with one another to prevent the blade 50 from escaping the case 40 upon the blade 50 separating from the shaft 52. The blanket 54 is at least partially impregnated with shear thickening fluid.
The exemplary compressor section 16 can also define a third embodiment. A high-pressure (HP) compressor blade 56 can be engaged with an HP shaft 58 for rotation about the axis 24. The case 40 is positioned radially outward of the blade 56 and the HP shaft 58. A blanket 60 is mounted to the case 40. The case 40 and the blanket 60 are operable to cooperate with one another to prevent the blade 56 from escaping the case 40 upon the blade 56 separating from the shaft 58. The blanket 60 is at least partially impregnated with shear thickening fluid.
The exemplary turbine section 20 can define a fourth embodiment. A high-pressure (HP) turbine blade 62 can be engaged with the HP shaft 58 for rotation about the axis 24. The case 40 is positioned radially outward of the blade 62. A blanket 64 is mounted to the case 40. The case 40 and the blanket 64 are operable to cooperate with one another to prevent the blade 62 from escaping the case 40 upon the blade 62 separating from the shaft 58. The blanket 64 is at least partially impregnated with shear thickening fluid.
The exemplary turbine section 20 can also define a fifth embodiment. A low-pressure (LP) turbine blade 66 can be engaged with the LP shaft 52 for rotation about the axis 24. The case 40 is positioned radially outward of the blade 66. A blanket 68 is mounted to the case 40. The case 40 and the blanket 68 are operable to cooperate with one another to prevent the blade 66 from escaping the case 40 upon the blade 66 separating from the shaft 52. The blanket 68 is at least partially impregnated with shear thickening fluid.
All of the exemplary blades 44, 50, 56, 62, 66 are operable to direct a working fluid along the centerline axis 24 and are fan-like in operation. All of the embodiments described above can be practiced together. Alternatively, less than all of the embodiments described above can be practiced together. Further, embodiments of the invention can be practiced in operating environments other than turbine engines.
The exemplary blankets 48, 54, 60, 64, 68 are at least partially impregnated with shear thickening fluids. Shear thickening fluids are composed of relatively hard particles suspended in a liquid. The liquid can be polyethylene glycol, which is non-toxic and can withstand a wide range of temperatures. The particles can be nano-particles of silica. The combination of the liquid and the particles is flowable. Shear thickening fluid can be obtained from University of Delaware, Office of Vice Provost for Research, Newark, Del. 19716-6408 (http://www.ccm.udel.edu/STF/index.html). In addition, U.S. Pat. Nos. 7,226,878 and 7,498,276 are hereby incorporated by reference for their teachings of impregnating textiles with shear thickening fluids.
One or more of the blankets 48, 54, 60, 64, 68 can be at least partially formed from para-aramid synthetic fibers. Aramid fibers are a class of heat-resistant and strong synthetic fibers. The name is a shortened form of “aromatic polyamide.” The fibers having the chain molecules highly oriented along the fiber axis, so the strength of the chemical bond can be exploited. The Federal Trade Commission definition for aramid fiber is a manufactured fiber in which the fiber-forming substance is a long-chain synthetic polyamide in which at least 85% of the amide linkages, (—CO—NH—) are attached directly to two aromatic rings. Aramids are aromatic polyamides. The prefix “para” refers to the position of the carboxylic and amine groups on the monomer ring. Examples of para-aramid synthetic fibers include Kevlar® and Twaron®. Other kinds of fibers can be applied in other embodiments of the invention.
One or more of the blankets 48, 54, 60, 64, 68 can be formed from multiple layers of fabric stacked radially relative to the axis. The number of layers can be selected based on the possible impact load to be absorbed by the particular blanket. One or more of the blankets 48, 54, 60, 64, 68 can be formed from less or more than twenty-five layers.
Referring again to
The exemplary blankets 48, 54, 60, 64, 68 can fully encircle the respective cases 46 and 40.
The use of shear thickening fluids can be minimized if desired to reduce the cost of the blankets. Generally, the impregnated portion of the one or more of the blankets 48, 54, 60, 64, 68 can be positioned at position(s) that projectiles having the highest energy are likely to pass. A first approach to minimizing the use of shear thickening fluid can be to limit a width of a fully-impregnated blanket. For example, the width of the blanket 64 is substantially minimized along the axis 24 to substantially the distance that the blade 62 extends along the axis 24. A second approach can be to apply blankets with shear thickening fluid in combination with blankets without shear thickening fluid. For example, the blanket 48 can be at least partially impregnated with shear thickening fluid and can be positioned radially aligned with the blade 44 relative to the axis 24. A second blanket 92 can be mounted to the case 46, spaced along the axis 24 from the blade 44. The second blanket 92 can be positioned along a trajectory that the blade 44, if liberated from the hub 32, might pass. However, if the blade 44 passes toward the blanket 92 the energy of the blade 44 might be less than if the blade 44 passes toward the blanket 48.
A third approach can be to apply blankets only partially impregnated with shear thickening fluid.
A fourth approach to minimizing the use of shear thickening fluid can be to apply multiple blankets radially spaced from one another. Referring again to
While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. The right to claim elements and/or sub-combinations of the combinations disclosed herein is hereby reserved.
