Abstract:
In a method of manufacturing an electrode of a thermionic converter, a carbide layer is formed on a base material by a vapor synthesis, an N-type diamond layer doped with a donor impurity is formed on the carbide layer by a vapor synthesis, and a surface of the N-type diamond layer is terminated with hydrogen. The base material is made of a metal, and the carbide layer is made of a metal carbide.
Abstract:
In one aspect of the invention, a thermionic energy converter comprises an anode, a cathode spaced from the anode to define a gap therebetween, and molecular hydrogen incorporated into the gap.
Abstract:
A thermionic generator for converting thermal energy to electric energy includes: an emitter electrode for emitting thermal electrons from a thermal electron emitting surface when heat is applied to the emitter electrode; a collector electrode facing the emitter electrode spaced apart from the emitter electrode by a predetermined distance, and receiving the thermal electrons from the emitter electrode via a facing surface of the collector electrode; and a substrate having one surface. The emitter electrode and the collector electrode are disposed on the one surface of the substrate, and are electrically insulated from each other. The thermal electron emitting surface and the facing surface are perpendicular to the one surface.
Abstract:
A thermionic converter is disclosed comprising a single or multiple hot (emitter) and cold (collector) electrodes mounted side-by-side on a single substrate and a static electromagnetic for guiding electrodes from the emitter to the collector. The thermal path between emitter and collector electrodes is interrupted by cuts or trenches, and electrical connections to the electrodes are routed over a meander-like, high thermal resistance pathway cut into the substrate to further reduce thermal loss. In one embodiment, an Avto metal surface texture of nanoscale indents is provided on one or more of the electrodes to lower a work function. A method for fabricating said monolithic thermionic converter is further disclosed.
Abstract:
A method and apparatus for providing a source of power, comprising: a solid oxide fuel cell system and a thermionic device. The solid oxide fuel cell system provides a first source of power, wherein the solid oxide fuel cell system produces heat waste when the solid oxide fuel cell is providing the first source of power. The thermionic device for provides a second source of power, the thermionic device provides the second source of power from the heat waste which is provided to said thermionic device and an exhaust conduit provides fluid communication between an exhaust of the fuel cell system and a heat exchanger of the thermionic device.
Abstract:
Methods for fabricating nano-structured surfaces having geometries in which the passage of elementary particles through a potential barrier is enhanced are described. The methods use combinations of electron beam lithography, lift-off, and rolling, imprinting or stamping processes.
Abstract:
A thermionic converter having an emitter, a collector, and a source of cesium vapor is provided wherein the source of cesium vapor is differentially heated so that said source has a hotter end and a cooler end, with cesium vapor evaporating from said hotter end into the space between the emitter and the collector and with cesium vapor condensing at said cooler end. The condensed cesium vapor migrates through a porous element from the cooler end to the hotter end.
Abstract:
The present invention provides an alkali metal thermal to electric conversion cell having radially projecting beta-alumina type solid electrolyte elements and a central heat input region.
Abstract:
The present invention provides an AMTEC cell having a more robust power conductance path (conduction, radiation, convection, and latent heat transfer) from the heat input surface of the cell to the working fluid, evaporation surface, and SES. More particularly, one embodiment of the present invention includes collars, post and/or bridges extending between the SES support plate and the heat input surface. In another embodiment, a plurality of channels or conduits extend between the heat input surface and SES support plate. These embodiments simultaneously increase the thermal conductance path between the heat input surface of the cell and the evaporation surface as well as between the heat input surface of the cell and the SES, and enables superheating of the working fluid. Additionally, posts, fins or heat pipes may be provided in the low pressure zone of the cell between members of the SES to simultaneously increase the conductance between the heat input surface of the cell and the evaporation surface, raise the temperature of the SES, through radiation and/or conduction heat transfer, and isothermalize the SES. Furthermore, posts, fins, or heat pipes may extend from the heat input surface of the cell to a location proximate the SES on the high pressure side to simultaneously raise the temperature of the SES through radiation and conduction heat transfer, isothermalize the SES, and superheat the working fluid through convective heat transfer.
Abstract:
The present invention pertains to a stacked AMTEC module. The invention includes a tubular member which has an interior. The member is comprised of a ion conductor that substantially conducts ions relative to electrons, preferably a beta"-alumina solid electrolyte, positioned about the interior. A porous electrode for conducting electrons and allowing sodium ions to pass therethrough, and wherein electrons and sodium ions recombine to form sodium is positioned about the beta"-alumina solid electrolyte. The electrode is operated at a temperature and a pressure that allows the recombined sodium to vaporize. Additionally, an outer current collector grid for distributing electrons throughout the porous electrode is positioned about and contacts the porous electrode. Also included in the invention is transporting means for transporting liquid sodium to the beta"-alumina solid electrolyte of the tubular member. A transition piece is positioned about the interior of the member and contacts the transporting means. The transition piece divides the member into a first cell and a second cell such that each first and second cell has a beta"-alumina solid electrolyte, a first and second porous electrode and a grid. The transition piece conducts electrons from the interior of the tubular member. There is supply means for supplying sodium to the transporting means. Preferably the supply means is a shell which surrounds the tubular member and is operated at a temperature such that the vaporized sodium condenses thereon. Returning means for returning the condensed sodium from the shell to the transporting means provides a continuous supply of liquid sodium to the transporting means. Also, there are first conducting means for conducting electric current from the transition piece which extends through the shell, and second conducting means for conducting electric current to the grid of the first cell which extends through the shell.