Abstract: An electrohydrodynamic fluid accelerator includes an emitter electrode and leading surfaces of a collector electrode that are substantially exposed to ion bombardment. Heat transfer surfaces downstream of the emitter electrode along a fluid flow path include a first portion not substantially exposed to the ion bombardment that is conditioned with a first ozone reducing material. The leading surfaces of the collector electrode are not conditioned with the first ozone reducing material, but may include a different surface conditioning. The downstream heat transfer surfaces and the leading surfaces can be separately formed and joined to form the unitary structure or can be integrally formed. The electrohydrodynamic fluid accelerator can be used in a thermal management assembly of an electronic device with a heat dissipating device thermally coupled to the conditioned heat transfer surfaces.

Abstract: Performance of an electrohydrodynamic fluid accelerator device may be improved and adverse events such as sparking or arcing may be reduced based, amongst other things, on electrode geometries and/or positional interrelationships of the electrodes. For example, in a class of EHD devices that employ a longitudinally elongated corona discharge electrode (often, but not necessarily, a wire), a plurality of generally planar, collector electrodes may be positioned so as to present respective leading surfaces toward the corona discharge electrode. The generally planar collector electrodes may be oriented so that their major surfaces are generally orthogonal to the longitudinal extent of the corona discharge electrode. In such EHD devices, a high intensity electric field can be established in the “gap” between the corona discharge electrode and leading surfaces of the collector electrodes.

Abstract: In thermal management systems that employ EHD devices to motivate flow of air between ventilated boundary portions of an enclosure, it can be desirable to have some heat transfer surfaces participate in electrohydrodynamic acceleration of fluid flow while providing additional heat transfer surfaces that may not. In some embodiments, both collector electrodes and additional heat transfer surfaces are thermally coupled into a heat transfer path. Collector electrodes then contribute both to flow of cooling air and to heat transfer to the air flow so motivated. The collector electrodes and additional heat transfer surfaces may be parts of a unitary, or thermally coupled, structure that is introduced into a flow path at multiple positions therealong. In some embodiments, the collector electrodes and additional heat transfer surfaces may be proximate each other along the flow path. In some embodiments, the collector electrodes and additional heat transfer surfaces may be separate structures.

Abstract: Reversible flow may be provided in certain EHD device configurations that selectively energize corona discharge electrodes arranged to motivate flows in generally opposing directions. In some embodiments, a first set of one or more corona discharge electrodes is positioned, relative to a first array of collector electrode surfaces, to when energized, motivate flow in a first direction, while second set of one or more corona discharge electrodes is positioned, relative to a second array of collector electrode surfaces, to when energized, motivate flow in a second direction that opposes the first. In some embodiments, the first and second arrays of collector electrode surfaces are opposing surfaces of individual collector electrodes. In some embodiments, the first and second arrays of collector electrode surfaces are opposing surfaces of respective collector electrodes.

Abstract: An apparatus for cleaning an emitter electrode in electrohydrodynamic fluid accelerator and precipitator devices via movement of a cleaning device including complementary contoured cleaning surfaces positioned to frictionally engage and elastically deform the emitter electrode. The opposing cleaning surfaces laterally distort an otherwise linear longitudinal extent of the electrode under tension. The opposing cleaning surfaces are subject to wear, but maintain frictional engagement despite wear depths that exceed a radius of the electrode due at least in part to the at least partially complementary surface contours engaging the electrode under tension. The cleaning device causes respective cleaning surfaces to travel along a longitudinal extent of the emitter electrode to remove detrimental material and optionally to condition the electrode to at least partially mitigate ozone, erosion, corrosion, oxidation, or dendrite formation on the electrode.

Abstract: An apparatus for tandem cleaning of an emitter electrode and collector electrode in electrohydrodynamic fluid accelerator and precipitator devices via movement of a cleaning mechanism including respective cleaning surfaces positioned to frictionally engage the emitter electrode and collector electrode. The cleaning mechanism causes the respective cleaning surfaces to travel along a longitudinal extent of the emitter electrode and, in tandem, over a major dimension of the collector electrode to remove detrimental material from respective electrode surfaces. Alternatively, the electrodes can be transited in tandem in frictional engagement with a fixed cleaning mechanism in the same or opposite directions. A conditioning material is optionally deposited on an electrode to at least partially mitigate ozone, erosion, corrosion, oxidation, or dendrite formation on the electrodes. The conditioning material can include an ozone reducer.

Abstract: An electrohydrodynamic fluid accelerator includes an emitter electrode and leading surfaces of a collector electrode that are substantially exposed to ion bombardment. Heat transfer surfaces downstream of the emitter electrode along a fluid flow path include a first portion not substantially exposed to the ion bombardment that is conditioned with a first ozone reducing material. The leading surfaces of the collector electrode are not conditioned with the first ozone reducing material, but may include a different surface conditioning. The downstream heat transfer surfaces and the leading surfaces can be separately formed and joined to form the unitary structure or can be integrally formed. The electrohydrodynamic fluid accelerator can be used in a thermal management assembly of an electronic device with a heat dissipating device thermally coupled to the conditioned heat transfer surfaces.

Abstract: Embodiments of electrohydrodynamic (EHD) fluid accelerator devices utilize collector electrode structures that promote efficient fluid flow and reduce the probability of arcing by managing the strength of the electric field produced at the forward edges of the collector electrodes. In one application, the EHD devices dissipate heat generated by a thermal source in a thermal management system.

Abstract: In thermal management systems that employ EHD devices to motivate flow of air through an enclosure, spatial distribution of a ventilation boundary may facilitate reductions in flow resistance by reducing average transit distance for cooling air from an inlet portion of the ventilation boundary to an outlet portion. Some thermal management systems described herein distribute a ventilation boundary over opposing surfaces, adjacent surfaces or even a single surface of an enclosure while providing a short, “U” shaped, “L” shaped or generally straight through flow path. In some cases, spatial distributions of the ventilation boundary facilitate or enable enclosure geometries for which conventional fan or blower ventilation would be impractical.

Abstract: Reversible flow may be provided in certain EHD device configurations that selectively energize corona discharge electrodes arranged to motivate flows in generally opposing directions. In some embodiments, a first set of one or more corona discharge electrodes is positioned, relative to a first array of collector electrode surfaces, to when energized, motivate flow in a first direction, while second set of one or more corona discharge electrodes is positioned, relative to a second array of collector electrode surfaces, to when energized, motivate flow in a second direction that opposes the first. In some embodiments, the first and second arrays of collector electrode surfaces are opposing surfaces of individual collector electrodes. In some embodiments, the first and second arrays of collector electrode surfaces are opposing surfaces of respective collector electrodes.

Abstract: In thermal management systems that employ EHD devices to motivate flow of air between ventilated boundary portions of an enclosure, it can be desirable to have some heat transfer surfaces participate in electrohydrodynamic acceleration of fluid flow while providing additional heat transfer surfaces that may not. In some embodiments, both collector electrodes and additional heat transfer surfaces are thermally coupled into a heat transfer path. Collector electrodes then contribute both to flow of cooling air and to heat transfer to the air flow so motivated. The collector electrodes and additional heat transfer surfaces may be parts of a unitary, or thermally coupled, structure that is introduced into a flow path at multiple positions therealong. In some embodiments, the collector electrodes and additional heat transfer surfaces may be proximate each other along the flow path. In some embodiments, the collector electrodes and additional heat transfer surfaces may be separate structures.

Abstract: Performance of an electrohydrodynamic fluid accelerator device may be improved and adverse events such as sparking or arcing may be reduced based, amongst other things, on electrode geometries and/or positional interrelationships of the electrodes. For example, in a class of EHD devices that employ a longitudinally elongated corona discharge electrode (often, but not necessarily, a wire), a plurality of generally planar, collector electrodes may be positioned so as to present respective leading surfaces toward the corona discharge electrode. The generally planar collector electrodes may be oriented so that their major surfaces are generally orthogonal to the longitudinal extent of the corona discharge electrode. In such EHD devices, a high intensity electric field can be established in the “gap” between the corona discharge electrode and leading surfaces of the collector electrodes.

Abstract: The invention provides a “floating” port assembly of a receptacle of a transceiver. The configuration allows the transmitter port assembly to float conically (e.g., angularly from side to side and up and down) relative to the axial direction of the receptacle sleeve inside of the receptacle when a mechanical load placed on an optical fiber cable connected to the receptacle is transferred to the sleeve of the port assembly. The port assembly has a spring-return mechanism that biases the assembly such that it returns to its original center position when the load is removed. This floating isolates the ferrule of the optical fiber cable and the sleeve of the receptacle from external loadings transmitted via the fiber optic cable. Isolating the ferrule and the sleeve from the external loading dramatically reduces the effects of these external wiggle loads on the optical performance of the transmitter of the transceiver.

Abstract: An apparatus and method for switching optical signal is disclosed. An optical signal switch array includes a plurality of optical switches, each optical switch having a first trench adapted to hold index-matching fluid, and a second trench adapted to hold the index-matching fluid, but initially containing gas, the second trench connected to said first trench. A first expansion chamber is connected to the first trench, the first expansion chamber adapted to hold gas. A second expansion chamber is connected to the second trench, the second expansion chamber adapted to hold gas. To effect switching, the first expansion chamber is heated expanding gas in the first expansion chamber, the expanding gas shifting the index-matching fluid in the first trench to the second trench. Bistability is achieved by the use of capillary action, which passively holds the droplet of working fluid in either of two stable states until actuation.

Abstract: An apparatus and method for switching optical signal is disclosed. An optical signal switch array includes a plurality of optical switches, each optical switch having a first trench adapted to hold index-matching fluid, and a second trench adapted to hold the index-matching fluid, but initially containing gas, the second trench connected to said first trench. A first expansion chamber is connected to the first trench, the first expansion chamber adapted to hold gas. A second expansion chamber is connected to the second trench, the second expansion chamber adapted to hold gas. To effect switching, the first expansion chamber is heated expanding gas in the first expansion chamber, the expanding gas shifting the index-matching fluid in the first trench to the second trench. Bistability is achieved by the use of capillary action, which passively holds the droplet of working fluid in either of two stable states until actuation.