IMPEDANCE OF LONG SOLENOIDAL COILS. Technical Memo No. 54

Technical Report · Tue Jul 15 04:00:00 EDT 1958

OSTI ID:4260879

Tenney, F; Wells, D

An analysis was made of the impedance of long solenoidal coils as a function of frequency. The major difference between this calculation and Butterworth's is that the type of solenoid considered is very long and may have layers of different radial thickness that are an appreciable fraction of the radius. It was found that at increasing frequencies the current distribution in the inner layer approaches two sheet currents. Where two layers have a common boundary, there are two sheet currents flowing at this boundary in opposite senses and of equal strength. As a consequence, at high frequencies, the entire coil behaves inductively like a single sheet current at thc innermost radius. The coil sustains considerable losses at each layer boundary with the exception of the outermost where the current density falls toward zero. As a consequence the resistance is much larger than would be deduced by simple considerations of the conductor volume occupied by the current flow. (A.C.)

• Research Organization: Princeton Univ., N.J. Project Matterhorn
• DOE Contract Number: AT(30-1)-1238
• NSA Number: NSA-13-013393
• OSTI ID: 4260879
• Report Number(s): NYO-7993
• Country of Publication: United States
• Language: English

Related Subjects

COILS
CONTROLLED THERMONUCLEAR PROCESSES
CURRENTS
DENSITY
DISTRIBUTION
ELECTRIC CONDUCTIVITY
FREQUENCY
INDUCTION
LAYERS
LOSSES
OSCILLATIONS
SHEETS
SURFACES
THICKNESS