SUGGESTED MINIMUM
KNOWLEDGE OF FLUID
MECHANICS AND HEAT TRANSFER
FOR FE EXAM
F. Parsi
Winona State University
February 23, 2016
2 Hour Review
http://www.ncees.org/exams/study_materials/fe_handbook/
Exam Composition
• Morning
– 120 Questions
– 4 hours
– 7% Fluid Mechanics
• Afternoon (General Engineering)
– 60 Questions
– 15% Fluid Mechanics
Define and/or Explain
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density
specific gravity
specific volume
pressure (absolute and gage)
vapor pressure
shear stress
shear rate
viscosity (dynamic and kinematic)
Newtonian and non-Newtonian fluids
dimensional analysis
Fluid Statics
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u-tube manometer calculations
barometer calculations
hydrostatic pressure
force on submerged flat surface
point of application of the force
hydraulic ram
Buoyancy
Fluid Dynamics
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Reynolds number and its significance
laminar and turbulent flow
conservation of mass (continuity equation)
Bernoulli equation
head loss
major head loss calculations in pipes
friction factors (Moody and Darcy)
minor head loss calculations in piping systems
pumping power calculation
hydraulic radius
drag coefficient and drag force
Fluid Measurement Devices
• pitot tube
• venturi meters
• orifices
Example 1: Pressure
What is the atmospheric pressure on the
planet if the absolute pressure is 100 kPa
and a gage pressure is 10 kPa?
1. 10 kPa
2. 80 kPa
3. 90 kPa
4. 100 kPa
Example 2: static Pressure
What is the height of a column of tetrachloride
with a specific gravity of 1.56 that supports a
pressure of 1 lbf/in2?
1.
2.
3.
4.
5.
0.01 ft
0.12 ft
1.48 ft
1.56 ft
2.31 ft
Example 3: Viscosity
Kinematic viscosity cabn be expressed in
which of the following units?
1.
2.
3.
4.
m2/s
s2/m
kg.s2/m
kg/s
Example 4: Hydrostatic
Pressure
A pressure of 35 kPa is measured 4 m
below the surface of an unknown liquid.
What is the specific gravity of the liquid?
1.
2.
3.
4.
0.09
0.89
0.93
1.85
Example 5: u-tube manometer
The specific gravity of mercury is 13.6, and the
specific gravity of glycerine is 1.26. For the
manometer shown, calculate the difference in
pressure between points A and B.
1. 35 kPa
2. 42 kPa
3. 55 kPa
4. 110 kPa
Example 6: U-Tube Manometer
The fluid in a manometer tube is 60% water
and 40% alcohol (specific gravity = 0.8). What
is the manometer fluid height difference if a 6.2
lbf/in2 pressure difference is applied across
the two ends of manometer?
1.
2.
3.
4.
5.
0.92 in
15.5 in
186 in
215 in
361 in
Example 7: Fluid Statics
What is the resultant force on the inclined
wall?
1.
2.
3.
4.
222 kN
395 kN
503 kN
526 kN
Example 8: Fluid Statics
What is the vertical force on the inclined
wall?
1.
2.
3.
4.
197 kN
392 kN
486 kN
544 kN
Example 9: Hydrostatic Force
A tank is filled with water to a depth of 10
ft. What is the total force on the gate?
1.
2.
3.
4.
5.
560 lbf
5400 lbf
5620 lbf
6000 lbf
6240 lbf
Example 10: Buoyancy
A crown is made of an alloy of gold and silver.
The crown weighs 1000 g in air and 940 g in
water. What percentage of gold was it? Density
of gold and silver are respectively 19.3 g/cm3
and 10.5 g/cm3.
1. 53.1%
2. 67.4%
3. 81.2 %
4. 91.3%
Example 11: Buoyancy
A 24-in-long rod floats vertically in water. It has
a 1-in2 cross section and a specific gravity of
0.6. What length L, is submerged?
1.
2.
3.
4.
5.
2.4 in
9.6 in
14.4 in
18.0 in
18.7 in
Example 12: Fluid Dynamics
Consider water flowing through a converging
channel as shown and discharging freely into
the atmosphere at the exit. What is the gage
pressure at the inlet? Assume the flow to be
incompressible and frictionless.
1. 102 kPa
2. 106 kPa
3. 113 kPa
4. 127 kPa
Example 13: Dimensionless
Numbers
A 500-ft-long surface vessel is modeled at
1:50. What speed must the model travel if a 25
mph similarity is desired?
1.
2.
3.
4.
5.
3.54 ft/sec
5.0 ft/sec
5.2 ft/sec
7.07 ft/sec
7.3 ft/sec
Example 14: Hydraulic radius
The hydraulic radius is
1. The mean radius of the pipe
2. The radius of the pipe bend on the line
3. The wetted perimeter of a conduit divided
by the area of the flow
4. The cross-sectional fluid area divided by
wetted perimeter
Example 15: Hydraulic radius
What is the hydraulic radius of the shown
open channel?
1.
2.
3.
4.
b/4
b/3
b/2
2b/3
Example 16: Pipe flow
A steel pipe with an inside diameter of 25 mm is
20 m long and carries water at a rate of 4.5
m3/h. Assuming the specific roughness of the
pipe is 0.00005 m, the water has an absolute
viscosity of 1.00 x 10-3 m2/s and a density of
1000 kg/m3, what is the friction factor?
1. 0.023
2. 0.024
3. 0.026
4. 0.028
Example 17: Head Loss
What is the expected head loss per mile of
closed circular pipe (17-in inside diameter,
friction factor of 0.03) when 3300 gal/min of
water flow under pressure?
1.
2.
3.
4.
5.
0.007 ft
0.64 ft
38 ft
3580 ft
1.9x107 ft
Example 18: Pipe Flow
The transition between laminar and turbulent
flow in a pipe usually occurs at a Reynolds
number of approximately
1.
2.
3.
4.
5.
900
1200
1500
2100
3900
Example 19: Pumping Power
A pump requires 75 kW to move water with a
specific gravity of 1.0 at a certain flow rate to a
given elevation. What power does the pump
require if the flow rate and elevation conditions
are the same, but the fluid pumped has a
specific gravity of 0.8?
1. 45 kW
2. 60 kW
3. 75 kW
4. 90 kW
Basic Heat Transfer
• Conduction
• Convection
• radiation