Fluid Kinematics
Scalar
Vector
Scalar Fields
Vector Fields
Description of Fluid Motion
Description of Fluid Motion
Lagrangian Method:
 In this method, the fluid motion is described by tracing the kinematic behaviour of each and
every individual particle constituting the flow.
 Identities of the particles are made by specifying their initial position (spatial location) at a
given time.
Eulerian Method:
we specify the fluid properties (density, velocity, pressure...) at a fixed point
and a chosen time
it avoids the determination of the movement of each individual fluid
particle in all details
Relationship between the Eulerian and Lagrangian
Find the Lagrangian of the below Eulerian Problem
Integrate the above equation and
substitute initial conditions
Find the Lagragian of the below Eulerian
Problem
Material or Substantial Derivative
Material or Substantial Derivative
for any property
Types of flow
Developing Region and Fully Developed region
Turbulent Flow
In turbulent fluid flow, fluid particles move in a random and zigzag way. Turbulence is characterized by the
formation of eddies.
Streamlines
In a steady flow, streamlines, pathlines, and streaklines all coincide
Four Types of fluid motion:
Fluid element in pure Translation
Check whether the flow is compressible or
incompressible?
Fluid element in pure rotation