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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Iterative design procedure for optimum placement of vapor deposited Nb-Sn ribbon superconductors in high field large bore modular magnets
Electrical, and calorimetric measurements on alternating current loss in niobium zirconium, niobium titanium, and niobium stannide superconductors
Bare and insulated compound stabilized hard superconductors performance in unrestricted liquid He flow, noting flux flow, thermal stability, I-V characteristics and magnetoresistance
Temperature dependence of flux flow resistance near critical field in type 2 superconductors
Time dependent differential equation for order parameter in superconductors near critical temperature derived from density matrix equations
Surface to bulk nucleation critical fields ratio for semi-infinite pure superconductors
Critical currents, thermal equilibrium, magnetic flux jumps, and steady state stability of superconductors
Measuring magnetic flux flow and superconductor stabilization of thin and thick films
Thermodynamic and electrical properties of niobium stannide and other superconductors
Surface nucleation critical field for pure superconductors at temperatures outside Landau- Ginzburg region
Superconductor tubes experiment, observing flux jump initiation and propagation characteristics
Superconducting effects on alpha particle differential energy loss in tin, vanadium, and lead superconductors
Mathematical models for mixed state of superconductors
Flow measurement of magnetic flux in Nb-Zr superconductor to infer magnetic induction and currents in material
Voltage induction in superconductors by superimposed AC and DC magnetic fields
Method for processing Nb3Sn and other intermetallic compound superconductors produces a twisted, stabilized wire or tube which can be used to wind electromagnetics, armatures, rotors, and field windings for motors and generators as well as other magnetic devices.
Results of an experimental study of electrical losses in superconductor magnets. Preliminary 60-Hz ac loss data are presented for coils constructed of Nb3Sn ribbon, Nb-Ti cable, and multifilament Nb-Ti. Losses have been measured for different size coils up to approximately 20 cm in diameter. Of the conductor types tested, Nb3Sn ribbon has the lowest losses for ac operation. In Nb3Sn-ribbon coils of different sizes, the loss per unit length of conductor is shown to decrease with a decrease in the rate of change of current and to increase, in general, with increase in coil size. An important aspect of the study is the high degree of repeatability of the data.
The theoretical analysis of the Joule-heating power density in a specific hollow cylinder of a NbZr superconductor is presented. It is seen that the power density, which is the primary source of internal heating neglecting localized annihilation heating, can have a very complicated behavior, especially in the circular region. Rough estimates of the relative temperature changes are made, and the locations at which instabilities are more likely to initiate are considered.