MEEN 345 FINAL EXAM QUESTIONS AND VERIFIED
ANSWERS
Which of the followings is not the objectives of Lab 6? (Lab 6)
a) Determine the discharge coefficient of the flow through an orifice
b) Determine the contraction coefficient of the flow through an orifice
c) Determine the velocity coefficient of the flow through an orifice
d) Verify the relation between the head and the flow rate through an orifice
e) Determine the head loss through piping systems - Answers - e) Determine the head
loss through piping systems
Choose the location of the Vena Contracta from the flow through an orifice. (Lab 6)
a) 1 (at water level)
b) 2 (when the water leaves the free jet)
c) 3 (past where the water leaves the free jet) - Answers - b) 2 (when the water leaves
the free jet)
What is the use of the pointer in the picture? (Lab 6)
a) To measure the diameter of the jet
b) To measure the stagnation pressure of the jet
c) To locate the position of the Vena Contracta of the jet
d) To establish the datum line - Answers - a) To measure the diameter of the jet
What is the use of the Pitot tube in the picture? (Lab 6)
a) To measure the diameter of the jet
b) To measure the stagnation pressure of the jet
c) To locate the position of the Vena Contracta of the jet
d) To establish the datum line - Answers - b) To measure the stagnation pressure of the
jet
You predicted the flow rate through an orifice using continuity and Bernoulli's equation.
The actual flow rate was less than the predicted flow rate. What is the most probable
cause? (Lab 6)
a) The predicted result disregarded all frictional effects.
b) The predicted result assumed constant fluid properties.
c) The predicted result assumed uniform fluid velocity across the orifice.
d) The predicted result assumed incompressible and steady fluid flow. - Answers - a)
The predicted result disregarded all frictional effects.
, The volumetric flow rate, Q through the orifice is measured with the decreasing water
level, H in the tank. What is the relationship between the volumetric flow rate and the
pressure head in the tank? (Lab 6)
a) Q is proportional to H
b) Q is proportional to H^2
c) Q is proportional to H^1/2
d) Q is proportional to logH - Answers - c) Q is proportional to H^1/2
Which of the following is not an objective of Lab 7? (Lab 7)
a) Measure the mean pressure distribution around the circumference of a circular
cylinder for three fluid speeds
b) Use a multi-tube manometer system to measure the pressures distribution
c) Measure the drag force exerted on the cylinder by means of a force dynamometer
d) Calculate the net force on the cylinder due to the pressure distribution
e) Nondimensionalize the data to see how scaling works - Answers - c) Measure the
drag force exerted on the cylinder by means of a force dynamometer
The coefficient of pressure is a non-dimensional number to scale pressure
measurements from a model to a full sized item. Which of the following is an advantage
of a non-dimensional number? Select all that apply. (Lab 7)
a) It expresses the functional relationship between the variables in dimensionless terms.
b) It reduces the number of variables involved in a physical phenomenon.
c) The design curves can be developed from experimental data or direct solution of the
problem.
d) It allows to compare different systems by simplifying the problems in dimensionless
forms. - Answers - All of the above
A manometer that is filled with water (ρ=1000 kg/m3) is connected to an air duct to
measure the pressure inside the duct.The atmospheric pressure is 100 kPa. The
difference in the manometer level is 10 mm. Determine the absolute pressure in the
duct. (Lab 7)
a) 100.1 kPa
b) 99.9 kPa
c) 101 kPa
d) 99 kPa - Answers - b) 99.9 kPa
The following plot shows the pressure distribution on a cylinder that is placed in a flow.
What is the main reason why the experimental data are different from the theoretical
calculation? (Lab 7)
ANSWERS
Which of the followings is not the objectives of Lab 6? (Lab 6)
a) Determine the discharge coefficient of the flow through an orifice
b) Determine the contraction coefficient of the flow through an orifice
c) Determine the velocity coefficient of the flow through an orifice
d) Verify the relation between the head and the flow rate through an orifice
e) Determine the head loss through piping systems - Answers - e) Determine the head
loss through piping systems
Choose the location of the Vena Contracta from the flow through an orifice. (Lab 6)
a) 1 (at water level)
b) 2 (when the water leaves the free jet)
c) 3 (past where the water leaves the free jet) - Answers - b) 2 (when the water leaves
the free jet)
What is the use of the pointer in the picture? (Lab 6)
a) To measure the diameter of the jet
b) To measure the stagnation pressure of the jet
c) To locate the position of the Vena Contracta of the jet
d) To establish the datum line - Answers - a) To measure the diameter of the jet
What is the use of the Pitot tube in the picture? (Lab 6)
a) To measure the diameter of the jet
b) To measure the stagnation pressure of the jet
c) To locate the position of the Vena Contracta of the jet
d) To establish the datum line - Answers - b) To measure the stagnation pressure of the
jet
You predicted the flow rate through an orifice using continuity and Bernoulli's equation.
The actual flow rate was less than the predicted flow rate. What is the most probable
cause? (Lab 6)
a) The predicted result disregarded all frictional effects.
b) The predicted result assumed constant fluid properties.
c) The predicted result assumed uniform fluid velocity across the orifice.
d) The predicted result assumed incompressible and steady fluid flow. - Answers - a)
The predicted result disregarded all frictional effects.
, The volumetric flow rate, Q through the orifice is measured with the decreasing water
level, H in the tank. What is the relationship between the volumetric flow rate and the
pressure head in the tank? (Lab 6)
a) Q is proportional to H
b) Q is proportional to H^2
c) Q is proportional to H^1/2
d) Q is proportional to logH - Answers - c) Q is proportional to H^1/2
Which of the following is not an objective of Lab 7? (Lab 7)
a) Measure the mean pressure distribution around the circumference of a circular
cylinder for three fluid speeds
b) Use a multi-tube manometer system to measure the pressures distribution
c) Measure the drag force exerted on the cylinder by means of a force dynamometer
d) Calculate the net force on the cylinder due to the pressure distribution
e) Nondimensionalize the data to see how scaling works - Answers - c) Measure the
drag force exerted on the cylinder by means of a force dynamometer
The coefficient of pressure is a non-dimensional number to scale pressure
measurements from a model to a full sized item. Which of the following is an advantage
of a non-dimensional number? Select all that apply. (Lab 7)
a) It expresses the functional relationship between the variables in dimensionless terms.
b) It reduces the number of variables involved in a physical phenomenon.
c) The design curves can be developed from experimental data or direct solution of the
problem.
d) It allows to compare different systems by simplifying the problems in dimensionless
forms. - Answers - All of the above
A manometer that is filled with water (ρ=1000 kg/m3) is connected to an air duct to
measure the pressure inside the duct.The atmospheric pressure is 100 kPa. The
difference in the manometer level is 10 mm. Determine the absolute pressure in the
duct. (Lab 7)
a) 100.1 kPa
b) 99.9 kPa
c) 101 kPa
d) 99 kPa - Answers - b) 99.9 kPa
The following plot shows the pressure distribution on a cylinder that is placed in a flow.
What is the main reason why the experimental data are different from the theoretical
calculation? (Lab 7)
