Electroviscous effects, in chemistry of colloids and surface chemistry, according to an IUPAC definition, are the effects of the particle surface charge on viscosity of a fluid.
Viscoelectric is an effect by which an electric field near a charged interface influences the structure of the surrounding fluid and affects the viscosity of the fluid.
Kinematic viscosity of a fluid, ÷, can be expressed as a function of electric potential gradient (electric field), , by an equation in the form:
where f is the viscoelectric coefficient of the fluid.
The value of f for water (ambient temperature) has been estimated to be (0.5âÂÂ1.0) à10<sup>âÂÂ15</sup> V<sup>âÂÂ2</sup> m<sup>2</sup>.