2.1 INTRO TO FLUID FLOW Flashcards
What is Newton’s first law of motion?
Unless a force acts on a body, its velocity will not change.
If F=0, then change in u=0
Provides intuitive meaning of force: that agent which CHANGES the velocity of a body
What is Newton’s second law of motion?
The rate of change of momentum (mu) of a body, is proportional to the force that acts on it.
F = m.a
What is Newton’s third law of motion?
For any force exerted, there is an equal force in the opposite direction.
What is viscosity?
A measure of the resistance of a fluid to deformation e.g. shearing or extension.
(Simply, the resistance of a fluid to flow)
How do you obtain the kinematic viscosity v (nu)?
Divide the dynamic viscosity by density.
L^2T^-1 (L^2/T)
It is the ratio of dynamic viscosity to fluid density.
SI base units: kg m^-1 s^-1
What is the Bernoulli effect?
- Fluid velocity varies inversely with fluid pressure
- Demonstration with balloons; U2 > U1, P2>P1
- The sum of a pressure term, a velocity term and a gravitational/height term remain constant