Subsequently, this group explained that fluid motion occurs due to a Kelvin body force with two terms.
In contrast, the second is important only if there is a spatial gradient of the fluid susceptibility, e.g., in a non-isothermal system.
They showed that thermomagnetic convection can be correlated with a dimensionless magnetic Rayleigh number.
Recently, Kumar et.al [6] shed new light on the 20-plus year-old question of the appropriate tensor form of the Kelvin body force in Ferrofluids.
However, if the temperature distribution about the imposed magnetic field is asymmetric, so is the KBF in which case curl(ℑ) ≠ 0.