Transcript Thermodynamics I

Flow Measurement
 Pitot tube
* V = [ 2g ( P1-P2)/]1/2
 Orifice meter
• V = [ 2g ( h1-h2)/(1 – Co)] ½
• h = (P/ ) + Z
Homework
 Water flows through a 2-inch
diameter pipe at 200 lbm/min. Its
temperature is 60oF. Find the velocity
of water flow.
Homework
 Water from a pipe line is diverted into
weigh tank for exactly 9 minutes.
Tank weight increases 4765 lbf.
Water temperature is 60oF.
Homework
 Steady flow of gas through a pipe
whose diameter decreases from 1.0
meter to 60cm. The gas density
decreases from 2 kg/m3 to 1.6 kg/m3.
The entering velocity is 25 m/s.
What is exit velocity?
Reynolds Transport Theorem
 General energy equation: expands
Bernoulli Equation
Example
 System in figure carries water at rate
of 0.5 m3/s through a 50 cm diameter
pipe. Elevations are z2 = 40 m and z2
= 30 m. P1 = 70 kPa gage. . P2 must
be 350 kPa. The head loss through
the system is 3 m water. What
power must be supplied to the pump
kW & HP ?
References
Images & examples
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Mechanics of Fluids, 3rd Edition, Potter & Wiggert,
Brooks & Cole
Applied Fluid Mechanics, 6th Edition, Mott, Prentice Hall
Engineering Fluid Mechanics, 5th Edition Crowe, &
Roberson, Wiley
Fluid Mechanics Cengel & Cimbala McGraw Hill
Which of the examples
were helpful?