Fluid Properties Flashcards
What does surface tension allow for?
This allows small objects to float on water, even if they are denser, and enables the formation of droplets and bubbles.
What is surface tension?
Membrane that forms of the free surface of a fluid caused by intermolecular cohesive forces.
What are minor losses?
Friction losses that result from fittings (e.g. tees, elbows, and valves) in the line, changes in direction, and changes in flow area.
What is the hydraulic radius of a fluid conduit?
Cross-sectional area in flow divided by the wetted perimeter.
What is the basis of the Bernoulli equation for fluid flow?
Principle of conservation of energy
What is diffusion and how can it occur?
Diffusion is the movement of a defect from one point to another; it can occur through various mechanisms such as exchange and vacancy.
What does Fick’s First Law state?
Flux of diffusion is proportional to the negative volume concentration gradient; flux moves from high concentrations to low concentrations.
What is flux?
Flux is the amount of volume moving across a unit surface area in unit time.
What is the dimensionless number that relates inertial forces to viscous forces?
Reynolds number
What does the Nusselt number describe?
The ratio of convective heat transfer to conductive heat transfer.
What does the Prandtl number describe?
The ratio of momentum diffusivity to thermal diffusivity
What does the Biot number describe?
The ratio of internal and external heat transfer resistances.
What is the Froude number?
The ratio of inertial and gravitational forces.
What is the Stanton number?
The ratio of heat transferred into a fluid to the thermal capacity of the fluid.
What is the Reynolds number?
A dimensionless ratio of the momentum transferred by turbulence to the momentum transferred by molecular transport, or the ratio of inertial to viscous forces.
