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Drag Measurement of a Sphere in Helium II

Title: Drag Measurement of a Sphere in Helium II.
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Name(s): Hemmati, Ali, author
Van Sciver, Steven, professor directing thesis
Shih, Chiang, committee member
Hellstrom, Eric, committee member
Department of Mechanical Engineering, degree granting department
Florida State University, degree granting institution
Type of Resource: text
Genre: text
Issuance: monographic
Date Issued: 2009
Publisher: Florida State University
Place of Publication: Tallahassee, Florida
Physical Form: computer
Physical Form: online resource
Extent: 1 online resource
Language(s): English
Abstract/Description: An apparatus to measure the drag on an oscillating 3 mm niobium sphere in superfluid helium has been built and tested. A Nb-Ti superconducting solenoid is used to suspend the niobium sphere; meanwhile a similar superconducting quadruple magnet centers and helps to stabilize the ball at one location in the flow channel. The niobium sphere is levitated by the superconducting magnetic suspension system; then the oscillation is obtained by dropping the ball from one equilibrium point to a lower equilibrium point via reducing the magnetic field. The sphere's oscillation is then recorded with a high-speed CCD camera. The velocity of the sphere is then obtained by comparing the images captured and the distance the sphere has moved with time. Drag force is calculated through its relation to the maximum velocity decay rate. The sphere is contained within a closed end channel that allows measurements in liquid or gaseous helium and vacuum.
Identifier: FSU_migr_etd-4132 (IID)
Submitted Note: A Thesis submitted to the Department of Mechanical Engineering in partial fulfillment of the requirements for the degree of Master of Science.
Degree Awarded: Spring Semester, 2009.
Date of Defense: March 27, 2009.
Keywords: Drag Measurement, Magnetic Suspension, He II Turbulence
Bibliography Note: Includes bibliographical references.
Advisory Committee: Steven Van Sciver, Professor Directing Thesis; Chiang Shih, Committee Member; Eric Hellstrom, Committee Member.
Subject(s): Engineering
Mechanical engineering
Persistent Link to This Record: http://purl.flvc.org/fsu/fd/FSU_migr_etd-4132
Owner Institution: FSU