PDF Publication Title:
Text from PDF Page: 310
Hollow Cathodes 299 are found from the models discussed above, the insert life will be limited by evaporation in the same manner as in vacuum devices. Published measurements by Palleul and Shroff [51] of the depth of barium depletion in dispenser cathodes as a function of time and temperature show that barium depletion obeys a simple diffusion law with an Arrhenius dependence on temperature. This is shown in Fig. 6-44 (from [51]), where the impregnate surface layer in the pore recedes with time. The “activation energy” in the diffusion coefficient that determines the slope of the curves in Fig. 6-44 appears to be relatively independent of the cathode type. From data presented in Fig. 6-44, the operating time to deplete impregnate from the insert material to a depth of 100 m is ln 100μm =eVa +C1=2.8244e 15.488, (6.8-3) kT kT where the operating time 100 μ m is in hours, e is the elementary charge, Va is the activation energy, k is Boltzmann’s constant, C1 is a fit coefficient, and T is the insert temperature in kelvins. The activation energy was found from Fig.6-44. Using this relationship and the fact that the depletion depth is 103 102 101 S-Type Cathode S-Type Cathode B-Type Cathode B-Type Cathode 1035 CB 1230 CB 1050 CB 1250 CB 102 103 104 105 Time (hr) Fig. 6-44. Depletion depth of a porous tungsten insert as a function of time for cathodes at different temperatures (redrawn from [51]). Depleted Depth ( m) Square-Root SlopePDF Image | Fundamentals of Electric Propulsion: Ion and Hall Thrusters
PDF Search Title:
Fundamentals of Electric Propulsion: Ion and Hall ThrustersOriginal File Name Searched:
Goebel__cmprsd_opt.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)