MEASURING THE THERMAL CONDUCTIVITY AND THE ELECTRICAL CONDUCTIVITY OF A FERROFLUID IN A MAGNETIC FIELD.

The effect of a magnetic field on the transfer properties of ferrofluids is important, inasmuch as it has been hypothesized that these properties can be controlled by means of a magnetic field. Accordingly, a project was undertaken to measure the thermal conductivity lambda and the electrical conductivity sigma of a ferrofluid (magnetite dispersion in kerosene stabilized with olein) so as to establish whether a magnetic field affects these properties. The thermal conductivity was measured by the relative variant of the hot-wire method. Schematic diagram for measurement of electric conductivity is given. Results indicate the high stability of the ferrofluid and the absence of noticeable structural changes in the system upon application of a magnetic field.