摘要:
A compressor tip clearance management system includes a compressor section having a low pressure compressor and a high pressure compressor arranged downstream from the low pressure compressor. A variable stator vane is arranged upstream from the high pressure compressor. The variable stator vane is connected to an actuator, and a controller is in communication with the actuator. The controller is configured to provide a command to the actuator to move the variable stator vane in response to a high pressure compressor clearance condition. A high pressure compressor rotor speed is altered, and the high pressure compressor clearance condition is changed to a desired clearance.
摘要:
A core flowpath through a low pressure compressor section of a gas turbine engine includes an outer diameter, which has a slope angle relative to an axis defined by the core flowpath. The slope angle is a slope angle that is operable to prevent flow separation of a fluid passing through the core flowpath.
摘要:
A method for integrating an operating system (OS) into a basic input output system (BIOS) chip and to boot a computer using programs stored in the BIOS. A bootable image file of the OS is integrated with a virtual disk program and other BIOS instructions and stored into the BIOS chip. When the computer is powered up and upon the condition that an OS in a hard disk of a computer system is damaged, the OS in the BIOS chip is executed.
摘要:
The present invention relates to a method for preparing a neodymium-iron-boron rare-earth permanent magnetic material, in particular to a hot press molding-based method for preparing a rare-earth permanent magnet. The problem that the residual magnetism and coercive force of a rare-earth permanent magnet prepared in the prior art cannot be both high is solved. An RTM alloy infiltrates same during an HD treatment. RTM sticks to the surface of coarse powder and infiltrates into the interior of the coarse powder along a grain boundary. The temperature of hot press sintering is relatively low, and grains barely grow. In the absence of Dy and Tb, a higher coercive force is obtained. If an alloy containing Dy and Tb is used for infiltration, these atoms diffuse into the surface layer of a main phase during preheating and heat treatment, achieving grain boundary hardening. Under the premise of a very small reduction in the residual magnetism, the coercive force is greatly improved.
摘要:
A method of designing an airfoil for a gas turbine engine according to one embodiment of this disclosure can include localizing a sweep angle at a leading edge of a tip region of the airfoil, and localizing a dihedral angle at the tip region of the airfoil. The dihedral angle can be applied by translating the airfoil in direction normal to a chord of the airfoil.
摘要:
A rotor blade for a gas turbine engine includes an airfoil that extends in span between a root and a tip region. A leading edge and a trailing edge of the airfoil section extend between a chord line of the airfoil. A sweep angle is defined at the leading edge of the airfoil section, and a dihedral angle is defined relative to the chord line of the airfoil section. The sweep angle and the dihedral angle are localized at the tip region of the airfoil section.
摘要:
A method for integrating an operating system (OS) into a basic input output system (BIOS) chip and to boot a computer system using an image file stored in a server. A bootable image file of the OS is integrated with a virtual disk program and other BIOS instructions and stored into the BIOS chip. When the computer system is powered up, the OS stored in the BIOS can be booted to allow the another OS stored in the server to be downloaded into the harddisk and executed. The BIOS OS can also allow an OS stored on the local drive to be executed.
摘要:
A deoiler 26 for separating oil from air contaminated with the oil has at least one separator for separating the oil from the air and also has a source of suction for reducing air pressure at the source of the air. In an exemplary embodiment, the deoiler 26 creates the suction at a first operating condition, but acts as a restrictor at a second operating condition. A deoiling method according to the invention creates suction at a first operating condition to reduce the air pressure at the source of the oil-contaminated air, establishes a flow restriction at a second operating condition to pressurize the air source, and encourages oil to separate from the air at both operating conditions. When used as a component of a turbine engine lubrication system 22, the source of contaminated air may be a buffered bearing compartment 16. The inventive deoiler ensures a positive pressure difference across the bearing compartment seals 20 at the engine's idle power setting without requiring the idle setting to be undesirably high, and without requiring the use of buffer air whose pressure at higher engine power is high enough to be detrimental. In an exemplary embodiment, the deoiler pressurizes the bearing compartment at higher power settings to resist excessive buffer air infiltration into the bearing compartment.
摘要:
A scanning fluorescence lifetime microscope measures modulation and phase in fluorescence emission stimulated by spatially overlapped pump and probe beams operating at different frequencies. A pump laser modulated at a first frequency is focused onto a diffraction limited spot to excite a fluorescent sample under study. Simultaneously, a probe laser modulated at a second frequency is focused onto the same spot to induce a stimulated fluorescence emission in response to the optically combined output of the pump and probe laser light. Fluorescence emitted from the sample produces a cross-correlation signal which is dependent upon the spatial overlapping of the pump and probe beams at the focal point thereby producing a beneficial axial sectioning effect. Choosing a small differency frequency between the modulation of the first and second laser sources produces a low frequency cross correlation signal even when the modulation frequencies of the pump and probe lasers are very high. A signal processor obtains modulation and phase information from the low frequency cross correlation fluorescence signal allowing monitoring of even ultrafast fluorescence phenomena induced by high frequency modulation of the pump and probe lasers.
摘要:
A method of designing an airfoil for a gas turbine engine according to one embodiment of this disclosure can include localizing a sweep angle at a leading edge of a tip region of the airfoil, and localizing a dihedral angle at the tip region of the airfoil. The dihedral angle can be applied by translating the airfoil in direction normal to a chord of the airfoil.