Basics Flashcards
Types of approach in studying a control volume
1) lagrangian approach
2) Eulerian approach
Types of derivative
1) partial derivative
2) total derivative
3) substantial derivative
Classification of flow
1) steady/ unsteady
2) uniform/ non-uniform
3) laminar/ turbulence
4) compressible/ incompressible
5) rotational/ irrotational
6) potential flow
7) couette flow
Types of flow lines
1) stream line
2) path line
3) streak line
Fluid dynamics
1) kinematic
2) kinetics or dynamics
Fluid kinematic
Without considering the effect of force
Fluid kinetics
Considering the effect of force
Partial time derivative
Standing on a bridge and measuring fish concentration
Location is fixed
Total time derivative
1) moving on a boat and measuring fish concentration
Velocity of observer not equal to velocity of stream
Substantial time derivative/ material time derivative
Climb on a canon and observe the fish
Velocity of observer = velocity of stream
Reynolds number of flat plate
3*10^5 less than that - laminar
5*10^5 greater than that - turbulent
Reynolds number of Pipe
Less than 2000 laminar
Greater than 4000 turbulent
Reynolds number of packed bed
5 to 10 - laminar
Mach number
Inertial force/ elastic force
V/ velocity of sound
Compressibility
Mach > 0.2 compressible
< 0.2 incompressible
Rotational flow
Earth
Along stream line and own axis
Types of system
Open system / control volume system
Closed system / control mass
Isolate system
Archimedes principle
The buoyancy force on a body is equal to the weight of the fluid displaced by the body
Buoyancy force
It is the upward force exerted by the fluid against the weight of the body immersed
= density of fluid * gravity * volume of water displaced
