Accession Number : AD0290778

Title :   A HIGH PERFORMANCE D.C. MAGNET UTILIZING AXIAL COOLED DISCS

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE NATIONAL MAGNET LAB

Personal Author(s) : BRECHNA,H. ; MONTGOMERY,D.B.

Report Date : SEP 1962

Pagination or Media Count : 1

Abstract : Described is a water cooled magnet of the general Bitter type, which generates 130 kgauss at a power input of 1.75 megawatts. The magnet consists of a stack of 1 inch bore axial cooled discs and a surrounding shell of iron. The coil field is increased by about 10% by the use of 600 pounds of low carbon iron. Three cases of design are treated: (1) The radial temperature distribution is assumed to be constant. A hexagonal cooling pattern was introduced. The cooling holes have the same hydraulic diameter throughout the plates. (2) Due to the distribution of the cooling holes it can be shown that the temperature distribution is not constant and rises from the inner edge of the plates towards the outer edge. (3) A nonuniform temperature distribution in a coil is not desirable, especially with a high heat flux. The hot spot temperature determines the burnout power of the magnet. Discussed are the burnout heat flux limitation of the magnet and the magnetic stresses. Equipotential plots utilizing resistance plotting paper are shown to illustrate the flow of current around closely spaced cooling holes and the increase of effective resistance. It is shown that the current path follows a sinusoidal law. A table is given comparing calculations and measurements. The measured field of 130 kgauss was 2.5% less than the calculated field. (Author)

Descriptors :   *ELECTROMAGNETS, *SOLENOIDS, COOLING, DIRECT CURRENT, HEAT TRANSFER, IRON, MAGNET COILS, MAGNETIC FIELDS, PRESSURE, TEMPERATURE, THEORY

Distribution Statement : APPROVED FOR PUBLIC RELEASE