Abstract:
A pulse detonation device contains a pulse detonation combustor which detonates a mixture of oxidizer and fuel. The fuel is supplied through fuel ducts and the fuel flow is controlled by fuel flow control devices. Oxidizer flow is provided through a main inlet portion and a flow control device directs the oxidizer flow to either the combustor or to a bypass duct, or both. The combustor further contains an ignition source. Each of the flow control devices, fuel flow control devices and ignition source are controlled by a control system to optimize performance at different thrust/power settings for the device.
Abstract:
In one embodiment, a pulse detonation tube includes a continuous base tube having a substantially uniform wall thickness. The pulse detonation tube also includes a local flexural wave modifying feature configured to locally vary a flexural wave speed such that the flexural wave speed through the pulse detonation tube is different than an expected detonation wave speed, and/or to locally dissipate flexural wave energy.
Abstract:
A detonation chamber and a pulse detonation combustor including a detonation chamber, wherein the detonation chamber includes a plurality of initiation obstacles and at least one injector in fluid flow communication with each of the plurality of initiation obstacles. The plurality of initiation obstacles are disposed on at least a portion of an inner surface of the detonation chamber with each of the plurality of initiation obstacles defining a low pressure region at a trailing edge. The plurality of initiation obstacles are configured to enhance a turbulence of a fluid flow and flame acceleration through the detonation chamber. The at least one injector in provides a cooling fluid flow to each of the plurality of initiation obstacles, wherein the cooling fluid flow is one of a fuel, a combination of fuels, air, or a fuel/air mixture.
Abstract:
A pulse detonation combustor including a plurality of nozzles engaged with one another via mating surfaces to support a gas discharge annulus in a circumferential direction. The pulse detonation combustor also including multiple pulse detonation tubes extending for the nozzles and a plurality of thermal expansion control joints coupled to the plurality of pulse detonation tubes. Each of the plurality of thermal expansion control joints is configured to facilitate independent thermal growth of each of the plurality of pulse detonation tubes. The thermal expansion control joints may be configured as a bellows expansion joint or a sliding expansion joint.
Abstract:
A gas turbine engine augmentor includes at least one fluid based augmentor initiator defining a chamber in flow communication with a source of air and a source of fuel. The chamber includes a plurality of ejection openings in flow communication with an exhaust flowpath. The at least one fluid based augmentor initiator is devoid of any exhaust flowpath protrusions thereby minimizing any pressure drops and loss of thrust during dry work phase of operation. The source of fuel is operable for injecting fuel into the chamber such that at least a portion of the fuel flow is ignited at the plurality of ejection openings to produce a plurality of fuel-rich hot jets radially into the exhaust flowpath.
Abstract:
A flow control device for use with a pulse detonation chamber including an inlet coupled in flow communication with a source of compressed air. The inlet extends at least partially into the chamber to facilitate controlling air flow into the chamber. The device also includes a body portion extending downstream from and circumferentially around the inlet, wherein the body portion is positioned in flow communication with the inlet.
Abstract:
In one embodiment, a pulse detonation system includes a pulse detonation tube and an air valve disposed at an upstream end of the pulse detonation tube. The air valve is configured to provide an air flow into the pulse detonation tube. The pulse detonation system also includes a fuel injector configured to inject fuel into the air flow to establish a fuel-air mixture configured to support detonation, and to establish a region in the fuel-air mixture having a fuel to air ratio insufficient to support a detonation wave. The pulse detonation system further includes an ignition source configured to detonate the fuel-air mixture when the region is disposed adjacent to the air valve.
Abstract:
A pulse detonation combustor valve assembly is provided that includes a fixed valve portion having an inlet and a reciprocating valve portion. The valve assembly is coupled to a pulse detonation combustor. The reciprocating valve portion is exterior to the fixed valve portion and coaxially aligned with the fixed valve portion. The reciprocating valve portion is arranged to reciprocate with respect to the fixed valve portion to control inlet flow through the inlet of the valve assembly.
Abstract:
A method for operating a pulse detonation engine, wherein the method includes channeling air flow from a pulse detonation combustor into a flow mixer having an inlet portion, an outlet portion, and a body portion extending therebetween. The method also includes channeling ambient air past the flow mixer and mixing the air flow discharged from the pulse detonation combustor with the ambient air flow such that a combined flow is generated from the flow mixer that has less flow variations than the air flow discharged from the pulse detonation combustor.
Abstract:
An engine contains a compressor stage, a plurality of pulse detonation combustors and a rotary inlet valve structure having a plurality of inlet ports through which at least air flows to enter the pulse detonation combustors during operation of the engine. Downstream of the pulse detonation combustors is a turbine stage. Further, the ratio of the pulse detonation combustors to the inlet ports is a non-integer.