EGME 333 Fluid Mechanics
Final Review Problems
Fall 2020
Review Problems for Final
Look over the previous review problems from Midterm 1 and Midterm 2 and all the additioanl problems that you didn’t turn
in.
Problems from topics not covered on midterms 1 and 2:
3
in
1. Coffee flows through the filter shown in the figure at the right at a rate of 4 mugs
min = 60 min . Assume that the top
surface area of the filter basket and the surface area of the top of the liquid 4 in below the top are the same.
(a) Determine the loss coefficient for the filter
Answer: KL = 3 × 104
(b) Why is reasonable to neglect major losses? Show mathematically.
2. Water flows over the two plates shown. They have the same surface area, but have different shapes. (Note the pictures
show the plates as viewed from “above”.)
(a) Plate A
(b) Plate B
The height and width of square plate A is ` (i.e. each individual rectangle has width ` and height `/4)
(a) Determine the ratio of the drag on plate A to the drag on plate B. Assume laminar boundary layer flow.
Answer: DA /DB = 2
(b) Explain your answer physically.
(c) Why did I tell you to assume a laminar boundary layer? If I had not, what other information would you need to
complete part a.
kg
3. A smooth, spherical balloon of radius 4 m with total weight of 2625 N is rising through the air with density 1 m
3 and
−5 N ·s
viscosity 2 × 10 m2 . What is the terminal velocity?
Answer: V ≈ 0.624 m
s
4. A surfer (70 kg) is riding a surf board (30 kg) down the face of a wave inclined at 30◦ from the horizontal. The board
is rectangular with length ` = 3 m and width b = 1/3 m. The roughness divided by the board length is /` = 2 × 10−3 .
What is the steady speed of the board relative to water?
Answer: V ≈ 9.9 m
s
5. A regular 90◦ threaded elbow is used to connect two straight portions of 4 in diameter galvanized iron pipe.
(a) Determine the equivalent length of straight pipe for this elbow. For simplicity, assume that the Reynolds number
is high enough that the Darcy friction factor has reached its high-Re asymptote.
EGME 333 Fluid Mechanics
Final Review Problems
Fall 2020
Answer: 10.0 f t
(b) Use your answer to part (a) to judge whether the elbow has a significant or negligible effect on the head loss in
this system. Explain your reasoning in complete sentences.
Additional Problems from the book (8th edition)
Chapter 1: 34, 49, 72, 76,82
Chapter 2: 27, 28, 40, 45, 53, 60, 83, 92, 104
Chapter 3: 6, 8, 25, 33, 35, 48, 57, 75, 90
Chapter 4-7 see midterm 2 problems for additional problems listed
Chapter 8: 15, 20, 22, 27, 33, 39, 41, 50, 52, 68, 102
Chapter 9: 13, 21, 42, 45, 71, 77, 81, 97