USA As Represented by Secretary of the Navy

The United States of America As Represented by the Department of Health

Robert A Smith

Klaus C Schadow

Kenneth Jay Wilson

Timothy P Parr

Kenneth H Yu

Ephraim Gutmark

Phillip A Sprangle

Kwo R Chu

Richard A Stalnaker

Donna M Hanson-Parr

This invention involves an improved technique for the modulation of waste in an actively controlled compact waste incinerator afterburner. This improved technique utilizes acoustic driving to affect indirect modulation of waste flow velocities. The waste surrogate gases are modulated indirectly by periodic entrainment created by the roll-up of the main air vortex as well as indirect acoustic excitation of secondary air injection. One of the main advantages of this new configuration is the acoustic drivers used to phase inject the waste into the vortex for proper combustion are not in direct contact with the hot waste and therefore can be less expensive and more durable over the long term.

Apparatus for activity controlled waste incinerator afterburner

This invention involves an improved technique for the modulation of waste an actively controlled compact waste incinerator afterburner. This improved technique utilizes acoustic driving to affect indirect modulation of waste flow velocities. The waste surrogate gases are modulated indirectly by periodic entrainment created by the roll-up of the main air vortex as well as indirect acoustic excitation of secondary air injection. One of the main advantages of this new configuration is the acoustic drivers used to phase inject the waste into the vortex for proper combustion are not in direct contact with the hot waste and therefore can be less expensive and more durable over the long term.

Indirect modulation method for activity controlled waste incinerator

The present invention relates to an electric valve capable of producing podic mass-flow modulation of a gaseous, liquid, or mixed-phase medium over wide ranges of frequencies, pressure, and flow rates. Such mass-flow modulation can be used to periodically shed large-scale vortices at the outlet and to manipulate their dynamics allowing the user to actively control fluid mixing and transport further downstream. The device has a piezoelectric wafer that in a relaxed state abuts the upstream end of the outlet tube separating the pressurized fluid in the plenum with the outlet. The device has an apparatus for applying electric field to the wafer, which distorts the wafer and ruptures the seal forming a throat area that controls the fluid mass flux. Due to the fast response of the piezoelectric material to an electric field, the throat area can be modulated rapidly in time making the device operable even at high frequencies. The present invention is particularly useful for actively controlling fuel-air mixing in a combustor. However, it may be utilized in other applications such as in medical drug administration for inhalation therapy.

Mass-flux actuator with high frequency response

A shear layer of a fluid flow has relatively large vortical structures generated by acoustic forcing from oscillations induced in a cavity closely adjacent to the flow so that these structures enhance mixing at the layer. The forcing frequency is selected by varying the dimensions of the cavity, and several cavities of different dimensions may be provided for forcing at different frequencies, including beat frequencies. The cavity provides passive, high amplitude forcing effective with a compressible shear layer due to high speed flow, including supersonic flow. Cavities of differing configuration provide forcing for fluid flow from nozzles of different geometries. The most effective enhancement is provided by particular excitation frequencies generated by a cavity having a size selected in accordance with dimensionless relations between the flow parameters and nozzle geometry.

Enhancement of flow mixing by a frequency tunable cavity

An improved method and apparatus for actively controlling a combustion process such as a waste incinerator by means of a spatial and temporal synchronized injection of fuel. The improved method and apparatus employs an active control system which controls the intentional formation of large scale, coherent vortices and the synchronized injection of the fuel supply at various locations relative to the formation of the vortices. The preferred apparatus comprises an actuator or similar structure that is adapted for producing and stabilizing discrete, large scale vortices in a combustion device. In addition, another device controls or modulates the injection of the fuel into the vortices at the optimal location and timing relative to the vortex cycle. As applied to an incinerator, this method can be optimized to ensures that the fuel and waste are introduced into the highest temperature locations, were extended residence times are obtained by trapping the fuel and waste inside the vortices. A high combustion efficiency may also be achieved by actively synchronizing the periodic fuel injection with the formation of the vortices.

Method and apparatus for the active control of a compact waste

The oscillations found to occur in the cavities of an structural frame moving through a fluid are substantially eliminated by the adoption of perturbation elements located at the leading edge of the cavity and reflecting any remaining oscillations out of the cavity at the trailing edge. The perturbation elements may take the form of multiple pins of various shape and geometrical arrangement which prevents the generation and growth of vortices causing acoustic oscillations. The reflection of remaining oscillations out of the cavity may be accomplished by ramping the trailing edge of the cavity.

Suppressor of oscillations in airframe cavities

A regenerative liquid propellant gun and pertains includes a modified contional fixed bolt extending into a conventional combustion chamber of the regenerative liquid propellant gun. The modified fixed bolt of this invention provides for improved operation of the otherwise conventional regenerative liquid propellant gun and has modified end portion embodiments and internal propellant injection passages, all for the purpose of creating turbulent propellant flow.

Combustion instability suppression in regenerative liquid propellant gun

The invention is directed to a fluid mixing device in which a jet of first luid is passed through a nozzle having a conical inlet section and a noncircular, elongated, exit section. The jet of first fluid mixes with a second fluid located downstream of the device. In operation, the intersection of the conical and elongated sections produces axial rotation in the first fluid. Intense, three-dimensional, axial and circumferential vortical structures are created. These structures then interact with the high modes of azimuthal instabilities that are common to the elongated configuration. The jet of first fluid evolves into two secondary jets, generating a double shear layer inside the flow. Highly efficient mixing of the fluids, in both the outside and inside (core) segments of the jet, is achieved within a relatively small mixing space.

Fluid mixing device having a conical inlet and a noncircular outlet

An electron cyclotron maser high-frequency generator/amplifier having a cavity resonator positioned in an axial magnetic field. A spiralling beam of relativistic electrons is injected into the cavity and stimulated emission of radiation by the electrons takes place at the frequency of a wave mode supported by the cavity resonator. The transverse efficiency, defined as the average electron energy loss divided by its initial transverse energy, is maximized by disposing a shaped iron collar about the cavity resonator to provide an axial magnetic field in the cavity resonator whose amplitude increases in the beam direction-of-travel. In an alternative embodiment, the transverse efficiency is maximized by tapering the inner wall of the cavity in the axial direction to provide a wave-mode in the cavity resonator whose electric-field amplitude increases in the beam direction-of-travel.

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Ridgecrest, CA, United States of America

Robert A Smith