Non-ideal flow efficiency in magnetized coaxial accelerator channels

• Published in: 25th Anniversary, IEEE Conference Record - Abstracts. 1998 IEEE International Conference on Plasma Science (Cat. No.98CH36221) p. 162
• Main Authors: Mayo, R.M., Rohner, J.A., Black, D.C.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 1998
• Subjects: Acceleration; Accelerator magnets; Coaxial components; Electrons; Fluid flow measurement; Frequency; Magnetic variables measurement; Magnetization; Magnetohydrodynamics; Programmable logic arrays
• ISBN: 0780347927; 9780780347922
• ISSN: 0730-9244; 2576-7208
• DOI: 10.1109/PLASMA.1998.677583

Summary form only given. Recent results from the CPS-1 magnetized coaxial gun (MCG) experiment at NCSU demonstrate a technique for direct magnetic measurement of the local electron magnetization parameter (electron gyro-frequency normalized to the effective electron collision frequency) from which effective electron collisionality can be determined [Phys. Plas., 4 (1996) 3581]. The measurement technique also directly yields the magnetic Reynolds number without requiring independent flow measurements. From these quantities, we can infer the Morozov-Hall parameter (=ratio of the Hall to MHD terms=magnetization parameter/magnetic Reynolds number) again independent of flow measurements. Experimental results and non-ideal MHD modeling allow a more complete description of flow efficiency including resistive, magneto-resistive, and Hall losses. Improvements to earlier flow models include several important aspects of ion dynamics; high ion beta, radial ion losses, self-formed constrictions, ... Interestingly, in the presence of strong non-ideal mechanisms, the flow behaves nearly ideally. Experimental evidence and theoretical arguments will be presented for the competing and canceling influences of non-ideal effects.