Download or read book Survey of Materials for Thermionic Converters written by Arthur L. Smith and published by . This book was released on 1970 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Survey of Materials for Thermionic Converters written by Arthur L. Smith and published by . This book was released on 1970 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Voltage Thermionic Converters written by General Motors Corporation. Allison Division and published by . This book was released on 1964 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: Several emitter materials, tantalum, tungsten and rhenium, and two emitter geometries, planar and excess area were evaluated in a flexible laboratory thermionic converter design. Results are reported from six converters that were tested for a total of 1070 hr. Experimental results from the excess area emitter converters did not exhibit the current enhancement observed in multicapillary and slotted emitter converters developed on a previous Air Force contract. While the electron currents in the passive mode at relatively low cesium pressure were in qualitative agreement with theory, the actual current densities obtained were not high enough to produce practical power densities at high output voltage. The method of emitter fabrication which used a niobium braze material appears to be a primary reason for the low performance.
Download or read book A Review of the Output Performance of Six Planar Thermionic Converters with Various Electrode Materials written by Volney Colvin Wilson and published by . This book was released on 1971 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study of Materials for Thermionic Converters written by Harold Homonoff and published by . This book was released on 1963 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contents: Electrode Materials: Surface phenomena, Possible mechanism for (Ba, Sr) O cathode, Effect of purity and crystallographic plane, Properties of metalloids, New materials possessing a high or low work function; Adsorption on Semiconductors: Presence of surface states, Boundary layer phenomena; Development of Long Lived, Low Work Function Collectors for Cesium Thermionic Converters: Necessity for low work function collectors, Processing of collector, Thermochemical considerations.
Download or read book The Development of a Thermionic Converter Module Suitable for Liquid Metal Heating written by G. Y. Eastman and published by . This book was released on 1964 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Effort was continued to improve performance and increase the reliability of thermionic energy converters for space applications. The particular objectives include optimization of geometry and ceramic insulation between emitters and heat source. This work will include the development of a thermionic generator module to develop 3.0 volts of potential from a liquid metal heat source. The overall concept of the 3-volt generator has been established. Before final design and fabrication of the generator, the more difficult problems are being solved by fabricating and testing prototype 3-converter modules. During this period, four 3-converter modules were assembled. A number of subassemblies were successfully tested and techniques for assembling a series of converters within a single envelope were perfected. A method of bonding the center heat source tubing has been tentatively selected and materials for detailed evaluation of the method have been ordered. Life testing of one Type A1198B converter was concluded after 1010 hours. Another converter of this type has since completed 600 hours of a life test with a constant output of 46 watts. (Author).
Download or read book U S Government Research Reports written by and published by . This book was released on 1964 with total page 1600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Study of Materials for Thermionic Converters written by Harold Homonoff and published by . This book was released on 1963 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermionic Converter Surface Conditions written by V. C. Wilson and published by . This book was released on 1964 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report includes a short review of the program of work being undertaken and the status. The investigation of the operation of a parallelplane cesium converter having an emitter of oxygen-treated tantalum and a collector of molybdenum was completed. A technical paper covering this aspect of the program is included as Appendix I. (Author).
Download or read book Thermionic Converter Research Studies written by J. M. Houston and published by . This book was released on 1964 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work accomplished covered research studies of a cesium thermionic converter incorporating a thorium dispenser cathode, studies of electrode materials both polycrystalline and single crystal, and the development of research techniques associated with the thermionic converters. (Author).
Download or read book The Development of an Improved Thermionic Energy Converter written by and published by . This book was released on 1965 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book EMITTER MATERIALS STUDY THERMIONIC ENERGY CONVERTERS written by and published by . This book was released on 1962 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental program was conducted on selected emitter materials to determine their potential for use in low-temperature thermionic energy converters. One oxide emitter and four different dispenser types were evaluated in parallel plate and cylindrical geometry in both glass and metal ceramic construction. With respect to power density the various dispenser emitter types showed suitable and reasonably similar performance. Performance degradation was reversed in some of these diodes and its mechanism explored and explained.
Download or read book Thermionic Energy Converter written by Dr. Walter L. Knecht and published by . This book was released on 1960 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Survey of the State of art in Thermionic Power Conversion Diode Utilization written by General Electric Company. Power Tube Department and published by . This book was released on 1963 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study Program on Cesium Vapor Filled Thermionic Converters Having High Vacuum Work Function Emitter Materials written by A. J. Kennedy and published by . This book was released on 1963 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ruthenium, a material having relatively low neutron absorption cross section, was investigated both as an emitter and collector in a thermionic converter. Both hot pressed and plasma sprayed ruthenium emitters were found to behave like high vacuum work function materials (i.e., display high output current densities at relatively low cesium pressures). Significant differences were noted, however, in the performance of the two ruthenium emitters prepared by the different processes. The performance of the ruthenium emitters is compared to that of iridium and rhenium emitters. Generally, the ruthenium data shows a higher output power density, particularly at relatively wide (10 to 30 mil) interelectrode gaps. The ruthenium plasma sprayed collector assumes its minimum value at a temperature which is lower than that for a molybdenum collector by approximately 100K. The value of collector work function at optimum is indicated to be approximately equal for ruthenium and molybdenum. (Author).
Download or read book Literature Survey on the Surface Structures of Refractory Metals with Reference to the Thermionic Emission and Energy Converters written by Welville B. NOWAK and published by . This book was released on 1966 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thermionic converter directly transforms heat into electricity. The conversion efficiency of these devices is maximized when the emitter and collector surfaces have optimum work functions that are uniform over the surfaces. This implies a surface consisting of a single type of crystallographic plane. A review of the literature has been made with respect to the surface structures of the refractory metals and the treatments producing these structures. There is direct evidence that single crystals, properly treated, and that well-oriented, properly-treated polycrystalline material can provide surfaces with relatively uniform work functions. There is reason to believe that, with suitable chemi-thermal treatments and induced material transport, one could produce a uniform work function surface on randomly oriented, polycrystalline material. (Author).
Download or read book Thermionic Energy Conversion written by George N. Hatsopoulos and published by . This book was released on 1979-01 with total page 683 pages. Available in PDF, EPUB and Kindle. Book excerpt: Prepared under the auspices of the U.S. Department of Energy Division of Power Systems. Volume I of Thermionic Energy Conversiondealt with processes and devices (MIT Press, 1974). Its four chapters summarized information basic to the field and not subject to substantial alteration by future developments. Volume II begins with chapter 5 and describes the scientific and engineering aspects of thermionic conversion and the experience with actual operational hardware. It summarizes the experience and analytic methods that should be useful in the development of new applications of thermionic conversion. Thermionic Energy Conversionis intended for scientists and engineers working in the field of energy conversion. With increased interest in maximizing the efficiency of present energy conversion systems, it is an important reference for scientific and engineering libraries as well. The book benefits especially from the authors' actual experience-Hatsopoulos and his firm, Thermo Electron Corporation, are leaders in this field. Gyftopoulos and his students have made basic contributions to the theory of thermionic conversion. Both authors have developed a unified quantum theory of mechanics and thermodynamics. The book covers Elements of Quantum Mechanics; Principles of Thermodynamics; Thermodynamics of Stable Equilibrium States; Thermodynamics of Steady States; Emission Phenomena; Collisionless Transport Phenomena; Analysis of Performance Characteristics of High-Pressure Diodes; Experimental Techniques; Experimental Studies and Correlations of Characteristics; Metallurgy of Electrode Materials; Design and Fabrication of Practical Convertors; and Thermionic Power System Engineering.
