Accession Number : AD0618080

Title :   SUPERFLUID LIQUID HELIUM GYROSCOPE,

Corporate Author : MINNESOTA UNIV MINNEAPOLIS SCHOOL OF PHYSICS AND ASTRONOMY

Personal Author(s) : Mehl,J. B. ; Zimmerman,W. ,Jr.

Report Date : 1965

Pagination or Media Count : 4

Abstract : Persistent circulating currents of superfluid helium were observed by means of associated gyroscopic effects in an experiment. The gyroscope consists of a 3 cmdiameter glass sphere filled with powder, of particle size 0.001 cm, which forms fine channels through which the superfluid flows. The superfluid current is generated by steadily rotating the sphere about a vertical axis while cooling through the lambda-point and then stopping the sphere's rotation at a lower temperature. The sphere is mounted so that it subsequently can be tipped through 90 degrees about a horizontal axis and the vertical component of torque needed to carry out this tipping measured. By this means repeated measurements of the persisting angular momentum can be made, assuming the angular momentum to tip with the sphere. With an initial angular velocity of rotation of 0.28 radians/sec, measurements of a persisting angular momentum have been repeated up to 40 times during a period of 100 minutes showing no decay of the motion during that period to an accuracy of = 10%. (Author)

Descriptors :   (*LIQUEFIED GASES, HELIUM), (*HELIUM, FLUID DYNAMICS), (*FLUID MECHANICS, HELIUM), VORTICES, FLUID FLOW, GYROSCOPES, SPHERES, LOW TEMPERATURE

Distribution Statement : APPROVED FOR PUBLIC RELEASE