Ideal Fluid in Motion
1- Nonviscous flow.
In a nonviscous fluid, internal friction is neglected.
2. The flow is steady.
In steady (laminar) flow, the velocity of the fluid at each point remains constant.
3. The fluid is incompressible.
The density of an incompressible fluid is constant.
4. The flow is irrotational.
In irrotational flow, the fluid has no angular momentum about any point.