This is a draft cheat sheet. It is a work in progress and is not finished yet.
1. The fluid is Newtonian
2. Fluid is isotropic
3. Fluid is incompressible
4. Fluid flow is steady state
5. Fluid flow is laminar
6. Fluid flow is fully developed
7. No slip condition
Units and Conversions
1 Pa = 1 N/m2 = 1 kg/(m·s2)
1 atm = 101325 Pa = 2116.22 lbf/ft2
where n is the surface tension of the cell [N/m]
if given thickness then n = σt
Equal volumes feel equal buoyant forces.
Why? Identical pressure environments and equal water displacement.
Submerged Object: Archimedes' Principle
Mass of Object - Submerged Mass = Density of Fluid x Volume of Object
Submerge object water level increases
Remove object from boat water level decreases
Terms and Facts
A material property, gives proportionality of shear stress and shear rate [g/cm·s]
Non-Newtown Fluids: τ = μγη
Shear Thinning (η < 1)
Faster you shear it, thinner it becomes; resistance decreases, becomes more uniform.
Shear Thickening (η > 1)
Faster you shear it, thicker it becomes; resistance increases.
Bingham Plastic (τ=μγ+τ_y)
Acts like a solid until the sheet stress reaches a critical value
Centrioidal Moments of Inertia
xcp = -γ·Ixy·sinθ·Ixy/Pcg·A = -Ixy·sinθ/hcg·A
ycp = -γ·Ixx·sinθ·Ixy/Pcg·A = -Ixx·sinθ/hcg·A
F = γ·hcg·A = P·A
The center of gravity and center of pressure are different locations.
The force on the object occurs at the center of gravity.
The pressure on the object occurs at the center of pressure (use Ixx, and Ixy)
When calculating the moment: remember the reaction forces
Pressure = densitygravityheight = ρgh
If given N/m3 or lbf/ft3 then do not add gravity
Change in elevation change in pressure
Within a single fluid, pressure is constant along a height
Specific Gravy = [density of X] / [density of water]
move down (+), move up (-)
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