抄録
We carried out non-equilibrium Brownian dynamics analysis of a ferromagnetic colloidal system which is subjected to both shear flow and ac magnetic fields. Through this analysis, the following results were obtained: When the frequency of magnetic field is equal to angular velocity of the solvent fluid, the apparent viscosity drastically decreases and the value becomes negative. The negative viscosity phenomenon is caused by the transformation of the energy of ac magnetic fields into the rotational kinetic energy of particles.
