Patent Application
20080047425
The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:
The engine 22 includes an inertial inlet particle separator system 24. The engine 22 compresses atmospheric air to elevate the air pressure, adds thermal energy, and exhausts the compressed high pressure air through a series of turbines. The turbines extract work from the high pressure air, which in turn, drives the transmission 20. Typically, air is induced into the engine 22 under ambient conditions and is exhausted from the engine 22 at ambient conditions. When air is induced at lower pressures than ambient the engine works harder to produce the same amount of power that is created at ambient pressures. This increase in work may result in increased fuel consumption. The system 24 selectively operates to separate induced fluid into a particulate contaminated fluid and clean fluid during various contamination conditions to minimize air pressure loss and minimize fuel consumption.
Referring to
The particle separator drive system 28 may take the form of any selectively driven system such as that the inlet particle separator 26 is selectively driven by the engine 22. that is, the particle separator drive system 28 may be a transmission-type system which selectively engages and disengages the inlet particle separator 26 from the engine 22. Alternatively, the particle separator drive system 28 may be a separate drive system which may take the form of an electric motor or bleed air (pneumatic) driven system which may likewise be selectively engaged and disengaged such that the inlet particle separator 26 may be driven independent of engine 22 operations.
The controller system 32 communicates with the particle separator drive system 28 and the sensor system 30. The controller system 32 may include a microprocessor based controller such as a computer having a central processing unit, memory (RAM and/or ROM), and associated input and output buses. The controller 32 may alternatively or additionally be a subsystem of a central vehicle main flight control unit, an engine control unit, an interactive vehicle dynamics module, or a stand-alone controller. The controller 32 may also be a solid-state digital or analog logic device.
The controller system 32 communicates with the sensor system 30 to selectively engage the particle separator drive system 28 in response to signals sensed by the sensor system 30. The sensor system 30 may include avionics such as an altimeter 34, a radar altimeter 36, and/or a laser velocimetry system 38. The sensor system 32 may alternatively or additionally include other dedicated “sand sniffer” type sensors including an optical device 40, a thermocouple type device 42 and or other particle sensing systems.
In operation, the controller system 32 selectively engages and disengages the inlet particle separator 26 from the engine 22 in response to signals sensed by the sensor system 30. Preferably, the controller system 32 identifies a FOD-related flight regime in which the likelihood of FOD damage may be determined. One low FOD flight regime is a cruise flight regime in which the aircraft is traveling at altitude and at a relatively high speed such as, for example only, above 200 feet of altitude AGL (above ground level) and at greater than 60 knots indicated airspeed. Thus, when a pre-programmed FOD-related flight regime condition is met, e.g., aircraft above 200 feet of altitude AGL (above ground level) and at greater than 60 knots indicated airspeed, the controller system 32 disengages the inlet particle separator 26 from the engine 22 to provide increased engine power and associated engine fuel efficient.
In addition, the particle separator drive system 28 may be manually controlled by the pilot through a cockpit switch 44 such that the inlet particle separator 26 may be manually engaged and disengaged. Examples of a low-FOD flight regime in which manual disengagement may be proper may be hovering over a low FOD surface such as water or tarmac. Moreover, disengagement of the inlet particle separator 26 in these conditions will provide increased engine power and the associated lift capacity. The need for gaining even a small fraction of additional power has been previously established, an example being the engine throttle “beep” thumb switches located on the pilot's collective control, which fine tunes the electronic engine control to gain as much power as possible during high demand flight regimes, such as an out-of-ground-effect hover. The cockpit switch control in this invention could alternatively or additionally be incorporated into or next to the “beep” switches to optimize pilot intuitive understanding of their use and function.
It should be understood that relative positional terms such as “forward,” “aft,” “upper,” “lower,” “above,” “below,” and the like are with reference to the normal operational attitude of the vehicle and should not be considered otherwise limiting.
Although particular step sequences are shown, described, and claimed, it should be understood that steps may be performed in any order, separated or combined unless otherwise indicated and will still benefit from the present invention.
The foregoing description is exemplary rather than defined by the limitations within. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention.
