What is Fluid?

A fluid is a substance which deforms continuously when subjected to external shearing forces.

Types of Fluids

Ideal Fluid

An ideal fluid is one which has no viscosity, no surface tension and incompressible. Ideal fluid is only an imaginary fluid as all the fluids, which exists, have some viscosity

Real Fluid

An Real fluid is one which has viscosity ,surface tension & compressible Naturally available all fluids are real fluid. For Examples Kerosene, Petrol,water,air etc

Newtonian Fluid

A real fluids, in which the shear stress is directly proportional to the rate of shear strain or velocity gradient is known as Newtonian Fluids.

Non Newtonian Fluid

A real fluids, in which the shear stress is not proportional to the rate of shear strain or velocity gradient is known as Non-Newtonian Fluids. e.g. Printer ink,ketchup,paints, blood, mud, slurries, polymer solutions etc.

Different types of non-Newtonian fluids

Newtonian, n = 1, the viscosity does not change with shear rate.

Pseudo plastic, n < 1, the effective viscosity decreases with shear rate.

Dilatant, n> 1, the effective viscosity increases with shear rate.