Quiz Three Flashcards
How do you find the volumetric flow rate?
The volumetric flow rate is found by multiplying the cross sectional area by the average velocity
How is the mass flow rate calculated?
The mass flow rate is calculated by multiplying the volumetric flow rate by its density
Compare and contrast laminar flow and turbulent flow.
:Laminar flow moves slower than turbulent flow - this causes less friction so a velocity gradient forms. Turbulent flow is when all of the fluid flows at the same speed - it is faster than laminar flow
How can you tell the difference between laminar flow and turbulent flow?
Calculating Reynold’s number helps determine if the flow is laminar or turbulent - 4000: turbulent
How do you calculate Reynold’s number?
Reynold’s number is calculated by multiplying the inside diameter of the pipe by the average velocity and density and dividing that value by the viscosity
What ratio is Reynold’s number?
Reynold’s number is the ratio between the inertial forces and the viscous forces
How do you calculate the generalized Reynold’s number?
See continuity equation slides
What are the major and minor forces a pump must overcome to allow a fluid to flow?
The major forces are viscous forces and frictional forces while the minor force is the energy loss due to sudden contraction/expansion of the pipe
What are frictional forces dependent on?
Major frictional forces are dependent on the flow rate and the roughness of the pipe
How is the relative roughness factor calculated?
The relative roughness factor is calculated by dividing the roughness factor (epsilon) by the diameter
What is the Darcy equation and what does it measure?
The Darcy equation measured the amount of energy lost at the surface of the pipe - it is calculated by dividing the change of pressure by the density and equaling it to two times the friction factor times the length of pipe times velocity to the negative 2 power divided by the diameter
What is the Darcy equation for laminar flow?
The Darcy equation for laminar flow is the change in pressure is equal to thirty two times the velocity times the viscosity times length of the pipe divided by diameter squared
