1. Introduction to Fluid Mechanics

2. Fluids: Statics vs Dynamics

3. Atmospheric Pressure Pressure = Force per Unit Area
Atmospheric Pressure is the weight of the column of air above a unit area. For example, the atmospheric pressure felt by a man is the weight of the column of air above his body divided by the area the air is resting on
P = (Weight of column)/(Area of base)
Standard Atmospheric Pressure:
1 atmosphere (atm) lbs/in2 (psi) Torr (mm Hg) millibars = kPascals
1kPa = 1Nt/m2

4. Fluid Statics Basic Principles: Fluid is at rest : no shear forces
Pressure is the only force acting
What are the forces acting on the block?
Air pressure on the surface - neglect
Weight of the water above the block
Pressure only a function of depth

5. Units SI - International System Length Meter Time Sec Mass Kg
Temp 0K = 0C
Force Newton = Nt = 1 kg m / s2
Gravity 9.81 m/s2
Work = Fxd Joule = N-m
Power = F/t Watt = Joule/sec

6. Units English Length in Ft Time in Sec lbm (slug) - 1 slug = 32.2 lbm
Force - lb
Gravity ft/sec2
Work = slug-ft/s2

7. Properties of Fluids Density = r (decreases with rise in T)
mass per unit volume ( lbs/ft3 or kg/m3 )
for water density = 1.94 slugs/ft3 or 1000 kg/m3
Specific Weight = g (Heaviness of fluid)
weight per unit volume g = rg
for water spec wt = 62.4 lbs/ft3 or 9.81 kN/m3
Specific Gravity = SG
Ratio of the density of a fluid to the density of water
SG = rf / rw SG of Hg = 13.55

8. Ideal Gas Law relates pressure to Temp for a gas
P = rRT
T in 0K units
R = 287 Joule / Kg-0K
Pressure
Force per unit area:
lbs/in2 (psi), N/m2, mm Hg, mbar or atm
1 Nt/m2 = Pascal = Pa
Std Atm P = 14.7 psi = kPa = 1013 mb
Viscosity fluid deforms when acted on by shear stress
m = 1.12 x 10-3 N-s/m2
Surface tension - forces between 2 liquids or gas and liquid - droplets on a windshield.

9. Measurement of Pressure
Barometer (Hg) - Toricelli 1644
Piezometer Tube
U-Tube Manometer - between two points
Aneroid barometer - based on spring deformation
Pressure transducer - most advanced

10. Manometers - measure DP
Rules of thumb:
When evaluating, start from the known    pressure end and work towards the    unknown end
At equal elevations, pressure is    constant in the SAME fluid
When moving down a monometer,    pressure increases
When moving up a monometer,    pressure decreases
Only include atmospheric pressure on    open ends

11. Manometers P = g x h + PO Simple Example:
Find the pressure at point A in this open u-tube monometer with an atmospheric pressure Po
PD = g W x hE-D + Po
Pc = PD
PB = PC - g Hg x hC-B
PA = PB

12. Archimedes Principle: Will it Float?
Section 3: Buoyancy
Archimedes Principle: Will it Float?
The upward vertical force felt by a submerged, or partially submerged, body is known as the buoyancy force. It is equal to the weight of the fluid displaced by the submerged portion of the body. The buoyancy force acts through the centroid of the displaced volume, known as the   center of buoyancy. A body will sink until the buoyancy force is equal to the weight of the body.
FB = g x Vdisplaced
FB = gW x Vdisp
= Vdisp FB
W = FB FB