标题: 『Flomerics Fluids IQ Test Answers』 [打印本页] 作者: 说不清 时间: 2011-5-1 09:32 标题: 『Flomerics Fluids IQ Test Answers』 Flomerics Fluids IQ Test Answers
Dear :
Thank you for participating in our recent Fluids IQ Test. We hope that you found it a
challenging yet fun learning experience.
Per your request, here are the answers to the test. As always, if you have any questions,
please feel free to contact Flomerics at info@flomerics.com.
Kind Regards,
Flomerics
Question #1
A phenomenon used frequently in civil engineering applications to dissipate excess kinetic energy is the hydraulic jump. The critical non-dimensional quantity that governs whether a jump will form is the:
a) Grashof Number – Gr
b) Froude Number – Fr
c) Reynolds Number – Re
d) Euler Number – Eu
[Answer: B]
Question #2
What popular flow speed measuring device is illustrated here?
a) Concentric cylinder viscosimeter
b) Pitot tube
c) Anemometer
d) Venturi meter
[Answer B]
Question #3
The urban legend that declares bathtubs and toilets drain in opposite directions in the northern and southern hemispheres is probably based on a fluid mechanics professor exaggerating the strength of what flow phenomenon:
a) Coanda effect
b) Vortex shedding
c) Coriolis effect
d) Boundary layer growth
[Answer: C]
Question #4 A 1/20 scale model of a submarine is built for the purposes of determining the drag force in a water tunnel. To determine the drag force on the real submarine at 5 knots, the water tunnel velocity should be set to (assume the water tunnel uses seawater with equivalent fluid properties):
a) 2.5 knots
b) 5 knots
c) 10 knots
d) 100 knots
[Answer: D]
Question #5
To determine the drag force on the real submarine, take the water tunnel measurement for drag and:
a) multiply by 20
b) multiply by 400
c) multiply by 1
d) divide by 20
[Answer: C]
Question #6 Which of the following quantities decreases across a normal shock line for an ideal gas:
a) Stagnation Temperature
b) Temperature
c) Pressure
d) Stagnation Pressure
[Answer: D]
Question #7 A fully developed flow within a circular pipe will remain laminar until the Reynold's number exceeds approximately:
a) 250
b) 2300
c) 50000
d) 100000
[Answer: B]
Question #8
If a water pump operating at 1400 RPM has a stagnation pressure of 100 inches H2O, what will the stagnation pressure be at 2800 RPM?
a) 100 inches H2O
b) 200 inches H2O
c) 300 inches H2O
d) 400 inches H2O
[Answer: D]
Question #9 Which of the following is true. Moody's famous chart for use in flow through pipes indicates:
a) Relative roughness does not effect the friction factor in the Transition zone
b) An increase in Reynold's number always yields a smaller friction factor
c) Reynold's number does not effect the friction factor in the Laminar Flow zone
d) Relative roughness does not effect the friction factor in the Laminar Flow zone
[Answer: D]
Question #10
The chart below shows a plot of drag coefficient vs Reynold's number for flow over a long cylinder. The dip after Re = 105 is attributed to:
a) Onset of turbulence in the boundary layer
b) Boundary layer separation
c) Vortex shedding
d) Decrease of viscosity at lower downstream pressures
[Answer: A]
Question #11
A Centipoise is a unit used to measure:
a) Pressure
b) Specific heat
c) Flow rate
d) Viscosity
[Answer: D]
Question #12 The governing equations of fluid flow are known as the:
a) Reynold's Transport Theorem
b) Euler Equations
c) Bernoulli's Equation
d) Navier-Stokes Equations
[Answer: D]
Question #13 The speed of sound in an ideal gas is given by this formula is:
a) The ratio of specific heats
b) Universal gas constant
c) Specific enthalpy of the gas
d) Bulk modulus of the gas
[Answer: A]
Question #14
Which of the following represents a dimensionless heat transfer coefficient
a) Nusselt Number – Nu
b) Strouhal Number – St
c) Laplace Number – La
d) Grashof Number – Gr
[Answer: A]
Question #15
At approximately what Mach number are compressibility effects no longer negligible (flow should not be considered incompressible)?
a) 0.05
b) 0.3
c) 0.8
d) 1.0
[Answer: B]
Question #16 The Prandtl number for water divided by the Prandtl number for air is approximately:
a) 0.1
b) 1
c) 10
d) 100
[Answer: C]
Question #17 Which of the following is not a model to simulate non-Newtonian liquid flow?
a) Herschel-Bulkley
b) Power Law
c) Favre-Hirsch
d) Carreau
[Answer: C]
