Electroviscous effects
Encyclopedia
Electroviscous effects, in chemistry
of colloid
s 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 effects the viscosity of the fluid.
Kinematic viscosity of a fluid, η, can be expressed as a function of electric potential gradient, E, by an equation in the form:
where f is the viscoelectric coeffcient of the fluid.
The value of f for water (ambient temperature) has been estimated to be (0.5–1.0) × 10–15 V–2 m2.
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....
of colloid
Colloid
A colloid is a substance microscopically dispersed evenly throughout another substance.A colloidal system consists of two separate phases: a dispersed phase and a continuous phase . A colloidal system may be solid, liquid, or gaseous.Many familiar substances are colloids, as shown in the chart below...
s and surface chemistry, according to an IUPAC definition, are the effects of the particle surface charge
Surface charge
Surface charge is the electric charge present at an interface. There are many different processes which can lead to a surface being charged, including adsorption of ions, protonation/deprotonation, and the application of an external electric field...
on viscosity
Viscosity
Viscosity is a measure of the resistance of a fluid which is being deformed by either shear or tensile stress. In everyday terms , viscosity is "thickness" or "internal friction". Thus, water is "thin", having a lower viscosity, while honey is "thick", having a higher viscosity...
of a fluid.
Viscoelectric is an effect by which an electric field
Electric field
In physics, an electric field surrounds electrically charged particles and time-varying magnetic fields. The electric field depicts the force exerted on other electrically charged objects by the electrically charged particle the field is surrounding...
near a charged interface
Interface (chemistry)
An interface is a surface forming a common boundary among two different phases, such as an insoluble solid and a liquid, two immiscible liquids or a liquid and an insoluble gas. The importance of the interface depends on which type of system is being treated: the bigger the quotient area/volume,...
influences the structure of the surrounding fluid and effects the viscosity of the fluid.
Kinematic viscosity of a fluid, η, can be expressed as a function of electric potential gradient, E, by an equation in the form:
- η=η0(1+f E2),
where f is the viscoelectric coeffcient of the fluid.
The value of f for water (ambient temperature) has been estimated to be (0.5–1.0) × 10–15 V–2 m2.