Abstract: An annular heat exchanger for a gas turbine engine is provided. The annular heat exchanger can include a first annular ring comprising a first main tube defined by a plurality of transduct segments; a second annular ring comprising a second main tube defined by a plurality of transduct segments and a curvilinear plate defining at least one channel therein that is in fluid communication with a transduct segment of the first main tube and a transduct segment of the second main tube.

Abstract: A transduct segment, that can include a main tube extending from a first end to a second end and defining a hollow passageway therethrough, a lower platform attached to an outer surface of the main tube on first side of an aperture defined within the main tube, and an upper platform attached to the outer surface of the main tube on second side of the aperture that is opposite of the first side, is provided. The upper platform is integral with the lower platform to define a supply channel therebetween, and the supply channel is in fluid communication with the hollow passageway of the main tube through the aperture defined by the main tube. The lower platform and the upper platform define an interface defining a plurality of channels in fluid communication with the hollow passageway defined by the main tube.

Abstract: A curvilinear plate for a heat exchanger is provided. The curvilinear plate can include an inner plate defining a plurality of first grooves and an outer plate defining a plurality of second grooves. The outer plate is attached to the inner plate with the plurality of first grooves and the plurality of second grooves substantially aligned to define a plurality of channels therebetween. Each channel extends from a first opening on a first portion of a first end of the curvilinear plate to a second opening on a second portion of the first end. A method is also generally provided for forming a curvilinear plate.

Abstract: A cross-flow heat exchanger for gas turbine engines which may be utilized to transfer heat from one fluid flow to a second independent fluid flow wherein one of the fluid flows has a high differential inlet pressure and temperature. The heat exchanger has robust construction to inhibit mixing of the fluid flows during a single burst duct event.

Abstract: A heat exchanger that includes an input cavity defined by inlet cavity walls; a heat exchanger portion in fluid communication with the input cavity and defined between a first side and a second side, and wherein a plurality of baffles are positioned within the heat exchanger portion; and an outlet cavity in fluid communication with the heat exchanger portion and defined by outlet cavity walls. The heat exchanger portion comprises: a plurality of first fluid paths defined between the baffles and extending from the input cavity to the outlet cavity, and a plurality of tubes extending through the heat exchanger portion from the first side to the second side. Each tube extends through the baffles so as to define a second fluid path through the heat exchanger portion. Heat exchanger systems are also generally provided, along with methods for cooling a hot fluid input with a heat exchanger.

Abstract: A method and system for a heat exchanger are provided. The heat exchanger includes a plurality of arcuate heat exchanger segments, each including a first header configured to extend circumferentially about at least a portion of a circumference of an internal surface of a fluid duct. The heat exchanger also includes a second header configured to extend circumferentially about the portion spaced axially apart from the first header in a direction opposite of fluid flow through the fluid duct and a first plurality of heat exchanger tubes extending generally axially between the first header and the second header, the first plurality of heat exchanger tubes each including a first flow path separate from a second flow path of any other of the first plurality of heat exchanger tubes, the first flow path changing direction along the flow path from the first header to the second header.

Abstract: Turbine engine assemblies including a turbine engine assembly having a turbine core comprising a compressor section, a combustion section, a turbine section, and a nozzle section, which are axially aligned, wherein the combustion section comprises a generally annular case having inner and outer walls, a heat exchanger comprising multiple passages in proximity to at least one of the inner and outer walls, with the passages arranged about at least a portion of the case and in fluid communication with each other such that fluid may flow through the passages and a cryogenic fuel system having a cryogenic fuel tank with a supply line coupled to one of the passages, wherein cryogenic fuel may be supplied from the cryogenic fuel tank, through the supply line, to the passages of the heat exchanger, where the fuel in the passages may be heated by the combustion section. The heat exchanger may be a single or multistage vaporizer.

Abstract: A superconducting coil mounted on, and in heat transfer relationship with, a heat conducting support cylinder. The superconducting coil is electrically insulated from the support cylinder by means of a refractory ceramic coating, such as aluminum oxide, on the surface of the cylinder or on an intermediate layer which itself is on the surface of the cylinder. To resist Lorentz forces, the superconducting coil may be positioned within a helical groove machined into the inside or outside surface of the cylinder.

Abstract: A superconducting energy storage inductor having two D-shaped coils with their flat sides being adjacent and facing one another. The coils are restrained from moving relative to one another and are immersed in a cryogenic fluid. The coils are connected in series and when provided with current, the resulting magnetic fields of the coils oppose one another.

Abstract: An acoustic projector wherein a unitary acoustic resonator produces active sonar signals in more than one frequency band. The double-slotted resonator is coupled to a transducer which is capable of exciting the resonator in two, distinct, volumetric modes of vibration using two asymmetric, generally arcuate vibrating members. Transduction techniques can include variable reluctance or piezoceramic transduction. Internal cavity pressure release may be achieved by bladders, compliant tubes, and the like.

Abstract: A sonar transmitter includes a source means for providing an actuation signal to drive an electromagnetic transducer projector without the use of bias magnetization. The invention utilizes an offset actuation frequency technique in which electrical driving signals are applied which have a frequency or frequencies other than the desired frequency of the acoustic signal projected into a liquid medium. In presently preferred embodiments, one or two driving signals may be utilized. If one driving signal is utilized, the acoustic signal will be at twice the driving signal frequency. If two driving signals are utilized, the acoustic signal will be at the sum or difference frequency of the driving signal frequency. The actuation signal is applied to coils of the transducer's electromagnets to produce an electromagnetic attractive force having a significant component at the desired frequency of the acoustic signal.

Abstract: A variable reluctance acoustic projector includes a piston structure that provides rigid retention and precise alignment of electromagnetic cores within the projector housing. The piston structure provides a pair of metallic piston blocks having cavities in which the electromagnetic cores are mounted. The piston blocks rigidly retain the electromagnetic cores within the cavities by compressive loading, improving the structural reliability of the device. In addition, the piston blocks enable precise alignment and orientation of the pole faces of opposing electromagnetic cores parallel to one another. Flexure ribs formed in the piston blocks increase the compliance of the blocks to substantially confine motion of the piston blocks to translation along a single axis of actuation during excitation of the electromagnetic cores.

Abstract: A structural support for cryogenic apparatus used in a vacuum vessel includes a plurality of spaced parallel plate members having honeycomb structures interposed therebetween and joined to the plate members. The honeycomb structure provides for a plurality of cells which are the same pressure existing within the vacuum vessel by reason of apertures being provided in the plate members or cell structures. The apertures are arranged so that they are offset from plate-to-plate or cell-to-cell in order that there be no direct optical path from the top of the support structure to the bottom or from side-to-side.

Abstract: An underwater acoustic projector including a Class IV flextension shell, preferably in the form of an ellipsoid, is connected to and driven by two substantially identical electromagnets having mutually opposing pole faces and having a common spatially uniform air gap which is centered between the pole faces. The coils of the two electromagnets are connected in series and when excited by a controlled current, generate a mutually attractive variable reluctance force which causes the pole faces to be attracted toward one another. The shell secured to the electromagnets elastically flexes along one of two mutually perpendicular axes resulting in a volumetric displacement of the outer surface of the shell.