PDF Publication Title:
Text from PDF Page: 148
136 Chapter 4 1 8kTe 1/2 e /kT –e 1/2 –1 Ia=4 m eneAae e 1 erf kT , (4.3-64) e where the potential is now a negative number. If the potential goes sufficiently negative relative to the anode, the current density can reach a factor of two higher than the one-sided random electron flux normally collected in order to satisfy the discharge current requirement. However, once the potential goes sufficiently negative relative to the anode to repel the ions (about Ti ), then the anode area for the plasma electron is not the hybrid area, but is just twice the plasma electron Larmor radius times the cusp length, similar to Eq. (4.3-3) for the primary loss area. This results in a significant decrease in the cusp anode area Aa in Eq. (4.3-63) for negative plasma potentials, which further lowers the plasma potential relative to the anode. Examining the potential distribution in the plasma in Fig. 4-22, the transition from the normal negative-going sheath to a negative plasma potential (positive-going anode sheath) will subtract from the primary electron energy Vpe at a given discharge voltage. The ionization rate then decreases, and the discharge collapses into a high impedance mode or oscillates between this mode and a positive potential typically on power supply time constants as the supply tries to reestablish the discharge by increasing the anode voltage. The stability of the plasma discharge at a given operating point (discharge current, beam current, neutral density in the discharge chamber, etc.) is therefore determined by the magnetic field design. For example, in Fig. 4-23, plasma potential is plotted as a function of the strength of the cusp magnetic field for an arbitrary thruster design with two different numbers of ring cusps. The cusp field strength enters into the anode area Aa in Eq. (4.3-6), into the primary electron loss area Ap in Eq. (4.3-3), and into the plasma potential in Eq. (4.3-63). The model predicts that a four-ring design would be unstable (when the potential goes negative relative to the anode) for cusp magnetic fields greater than 2000 G. Since strong magnetic fields are desirable from a primary electron and ion confinement point of view, additional rings are required to maintain a positive plasma potential. A six-ring design increased the anode area sufficiently to raise the plasma potential at the 2000-G magnet design point. An analysis of the discharge loss from Eq. (4.3-60) indicates that the improved stability associated with the larger anode area of the six-ring design comes with a loss in efficiency. The trade-off between efficiency and stability is an important aspect of ion thruster design.PDF 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 | RSS | AMP |