An oscillating superleak sound transducer
Tóm tắt
A resonator has been constructed in which a rigid superleak, fixed at one point across an annular cavity filled with liquid 4He, behaves as a differential filter for superfluid flow. The boundary conditions which obtain at the superleak determine the motion of the total fluid in the annulus and, by its reaction force on the superleak, the motion of the resonator as a whole. The condition for resonance motion of the resonator when driven (externally) by a periodic torque has given information about the temperature dependence of the superfluid density in the superleak which, in these experiments, was porous vycor glass.
Tài liệu tham khảo
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