摘要:
A method and system for assembly and attachment of high temperature materials used as thermal protection systems (TPS) for applications such as re-entry or hypersonic vehicles are disclosed. The attachment system comprises a fastener that passes through an aperture of and a fitting attached to a ceramic matrix composite (CMC) TPS panel. The flexure fitting allows thermal growth in the panel while providing a structurally stiff interface to support the panel through structural and acoustic loading. The flexure fitting is detachably attached to the substructure, or fuel tank of a vehicle. The fastened connection is accessed through an aperture via an access cover plate conformal to the surface of the CMC TPS panel. It is by way of the access cover that the fastened connection is externally serviced.
摘要:
An electrically-conductive, thermally-insulating structure includes a thermally-insulating layer having a thermal conductivity of no more than about 3.5null10null3 W/hrnullcmnullnull K and an electrically-conductive layer, applied to the thermally-insulating layer, which has an electrical resistivity of no more than about five ohms at 700null C. The thermally-insulating layer can comprise a plurality of microballoons to decrease the density of the thermally-insulating layer.
摘要:
A system and method for attaching an annular structural component to an aerospace vehicle is provided. The system includes a plurality of fittings circumferentially affixed to an engagement portion of the vehicle, and a plurality of supports. Each support has a first end connected to a corresponding fitting, and a second end having an elongate slot. A flange is configured to extend inwardly from the structural component and into engagement with the second end of each support. The flange has an elongate slot located at each support. Each flange slot is non-parallel to an open communication with each respective support slot. A plurality of pins connects the supports to the flange. Each pin extends through a corresponding flange slot and respective support slot to constrain the structural component, while attaching the structural component to the vehicle during use of the vehicle.
摘要:
A transpiration cooling system for avoiding overheating of an airfoil is provided. The airfoil is provided with a plurality of apertures and a source of pressurized fluid for providing a flow of fluid through the apertures to establish an aerodynamic radius. The aerodynamic radius of curvature of leading edge is sufficiently greater than the mechanical radius of curvature of the leading edge that peak heat flux is independent of the mechanical radius of curvature. The mechanical radius of curvature is preferably less than 50% of the aerodynamic radius of curvature during hypersonic operation. Preferably the mechanical radius of curvature is the smallest allowed by the fabrication method (i.e., a knife edge), such as being less than about 0.02 inches, preferably less than about 0.01 inches. The transpiration blowing rate can be adjusted so that the blowing rate and aerodynamic radius of curvature are relatively low except during periods of maximum heat flux, such as the shock-on-lip point. Since the mechanical radius of curvature is effectively zero, control of the aerodynamic radius of curvature provides complete control of peak heat flux. By adjusting blowing rate to the minimum necessary at any given velocity, transpiration consumption, drag and fuel injection are reduced or eliminated.
摘要:
An insulative panel is attachable to a structure to thermally protect the structure. The insulative panel includes a piece of a compliant, porous material. A support base is bonded to a first side of the piece of porous material, the support base including means for attaching the support base to the structure that is to be protected. A skin made of a thermally resistant material is bonded to a second side of the piece of porous material. Preferably, the porous material is a piece of porous ceramic foam having an apparent density of less than about 25 percent, the support base is a piece of nonporous ceramic material, and the skin is a ceramic thermal barrier coating that is plasma sprayed onto the porous material.
摘要:
An aircraft structure for the minimization of microwave energy reflection from the aircraft back to a receiver. The provision of structural configurations and materials operate to reduce microwave energy reflection toward its source or another receiver located at a level below the aircraft and laterally or forward thereof.
摘要:
The invention provides a system for selective reduction of infrared signature of a vehicle subjected to aerodynamic heating. Liquid coolant under pressure vaporizes in porous sections of the skin of the vehicle to transpiration-cool the skin. Adjacent downstream solid skin sections are film-cooled by the vapor introduced in the boundary layer. Coolant flow control is achieved by pressurizing the liquid coolant, by modulating flow control valves, and, optionally, by configuring the porous section to operate as a cavitating venturi, or combinations of these methods.
摘要:
An improved means for convection cooling the skin surfaces of an atmospheric flight craft such as are subject to air friction-induced overheating when the craft operates at high speed, featuring employment of multiple layered, spaced apart skin members separated and relatively braced by web and post members. Fresh coolant fluid is simultaneously flushed against and contiguously covers a multiplicity of relatively small patches of the inside surface of the outer skin member to be protected, and the spent coolant from each patch is separately removed therefrom and returned to the craft's refrigeration facility. The web and post members also act to direct the pattern of coolant flow so as to provide a much improved heat transfer coefficient than can be attained by other coolant path configurations when an equal pressure drop is applied.
摘要:
In order to dissipate aerodynamic heating in hypersonic aircraft, while at the same time providing structural support for the leading edge of an airfoil or the nose cone in a manner that avoids transmittal of thermal bending loads into the aircraft, a structural cooling unit is formed of a load bearing structure. The load bearing structure is of hollow construction defining a fluid flow path therethrough and has a fluid inlet at one end of the fluid flow path and a fluid outlet at the other end of the fluid flow path which comprises a tortuous path through the load bearing structure. Additionally, for purposes of forming a structural load path, the load bearing structure is formed into an elongated tubular configuration having at least one substantially continuous heat exchanging surface for aerodynamic heat dissipation.
摘要:
A cooled nosetip arrangement for a vehicle designed to travel at hypersonic velocities is taught herein. We provide a nosetip having one or more orifices at its forwardmost location, but instead of utilizing an arrangement for expelling a liquid coolant, which would necessitate a considerable amount of plumbing and tankage, we utilize a novel gas generator arrangement enabling a coolant gas to be selectively generated and then expelled from such nosetip orifice(s). In this manner we utilize a coolant that advantageously remains in a chemical form until it is to be actually utilized.