Magnetic Fluids Ferrofluid Torque Measurements in Alternating and Rotating Magnetic Fields
نویسنده
چکیده
Analyses and measurements have shown anomalous behavior of ferrofluids in alternating and rotating magnetic fields, including flow reversals and negative magnetoviscosities as a function of magnetic field amplitude and frequency. These experiments measure the ferrofluid viscous torque on a rotating cylinder while varying the magnetic field amplitude and frequency, thereby confirming the strong magnetic effect on the ferrofluid flow profile. The measurements in the work presented here are the first to report ferrofluid effective viscosities that are zero or negative.
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