Question

what is an ideal fluid

Answer 1

A fluid is a gas or liquid that, unlike a solid, flows to assume the shape of the container in which it is placed. This occurs because a fluid responds to a shear stress, or a force per unit area directed along the face of a cube of fluid, by flowing, rather than by an elastic displacement as in a solid.

Ideal fluid

An ideal fluid is a fluid that has several properties including the fact that it is:

• Incompressible – the density is constant

• Irrotational – the flow is smooth, no turbulence

• Nonviscous –(Inviscid) fluid has no internal friction ( η = 0)

Ideal fluid do not actually exist in nature, but sometimes used for fluid flow problems.

2.Real fluid: Fluid that have viscosity(μ > 0) and their motion known as viscous flow.

All the fluids in actual practice are real fluids.

Fluid dynamics:

we use ideal fluid in 2 equations :

1.Continuity equation

2.Bernoulli equation

3. Newtonian Fluids:

A real fluid in which the shear stress is directly proportional to rate of shear strain (or velocity gradient).

4. Non-Newtonian Fluid:

A real fluid in which the shear stress is not proportional to the rate of shear strain.

5. Ideal Plastic Fluid:

A fluid in which shear stress is more than the yield value and shear stress is proportional to the rate of shear strain (or velocity gradient

Answer 2

ideal fluid is
1. non viscous
2. non compressible
3. stream line flow (laminar flow)
4. irrotational