Density:r (kg/m³) 1400

The specific gravity is measured using a hydrometer, then converted to density. Temperature is a factor and must be accounted for.

Heat Capacity: Cp(J/kg K) 3000

The heat capacity is measured using a calorimeter.

Therm. Expansion Coeff: b (1/K) 2.60E-04

b is a measure of the density r change of T. It can be determined from the r ~T data from density measurements.

b =-1/r (¶r /¶ T)

Viscosity : m (kg/m s) 6.64E-03

Kinematic Viscosity: n=m/r (m²/s)

The viscosity of a magnetic fluid depends on the solid fraction f, the viscosity of the carrier fluid h₀ and the applied magnetic field (orientation as well as force). For the determination without an applie d magnetic field every standard viscometer can be used.

Thermal Conductivity: k (W/m K) 2.7

The thermal conductivity is measured using the hot wire technique. Two wires are immersed in fluid, one acts as a heat source, the other as a thermocouple.

Vortex / Rotational Viscosity: 

The vortex viscosity ,z orh_R , describes the damping due internal rotational friction. It can be measured using a torsional pendulum or estimated by:

(Shliomis 1972)

Pyromagnetic Coefficient: K (A/m K) 

Pyromagnetic coefficient K= -(¶ M/¶ T)_H, it is specified by three factors: temperature dependence of the Langevin argument x and magnetic moment of particles m, as well as fluid thermal expansion r (T). It can be calculated from the above relation and be simplified in specific cases

Time Constantt (s) 

There are two kinds of time constants. one is the relaxation time of the magnetic moment at a definite direction of the easy magnetization bilateral axis (t₀) which is determined by the magnetic moment range and of order 10^-7s, and the other is the Neel time of relaxation (t_N) which grows exponentially with increasing s and varies from 10^-8 to 10^-2s(s is dimensionless parameter, equal to the ratio of anisotropy energy to of thermal fluctuation).

Magnetic Susceptibilityc₀

quantitative measure of the extent to which a material may be magnetized in relation to a given applied magnetic field. The magnetic susceptibility of a material, commonly symbolized by c , is equal to the ratio of the magnetization M within the material to the applied magnetic field strength H, or c = M/H.