APPLIED FLUID MECHANICS (ME270/271)

Homework 11

Name:

CHAPTER 16

16-1 Figure 16.1 shows a free stream of water at 150oF being deflected by a stationary vane through a 120o angle. The entering stream has a velocity of 25 . The cross sectional area of the stream is constant at 3 in2 throughout the system. Compute the forces in the horizontal and vertical directions exerted on the water by the vane.

16-2 In a plant where hemispherical cup-shaped parts are made, an automatic washer is being designed to clean the parts prior to shipment. One scheme being evaluated uses a stream of water at 180oF shooting vertically upward into the cup. The stream has a velocity of 30 ft/s and a diameter of 1.00 in. As shown in Fig 16.2, the water leaves the cup vertically downward in the form of an annular ring having an outside diameter of 4.00 in and inside diameter of 3.8 in. Compute the external force required to hold the cup down.

Figure 16.1

Figure 16.2

16.1 à Rx = 37.11 lb Ry = 21.425 lb

Data Table

Deflector
Type
a
(degrees) / Volume
Collected
V
(lit) / Time to
Collect
t
(sec) / Mass
Applied
m
( g) / Deflector
Type
a
(degrees) / Volume
Collected
V
(lit) / Time to
Collect
t
(sec) / Mass
Applied
m
( g) / Deflector
Type
a
(degrees) / Volume
Collected
V
(lit) / Time to
Collect
t
(sec) / Mass
Applied
m
( g)
15 / 50 / 15 / 50 / 20 / 50
15 / 100 / 20 / 100 / 20 / 100
20 / 150 / 20 / 150 / 20 / 150
180o / 25 / 200 / 120o / 25 / 200 / 90o / 30 / 200
25 / 300 / 30 / 300 / 30 / 300
30 / 400 / 35 / 400 / 35 / 400
35 / 500 / 40 / 500 / 40 / 500

Results Table

Part a

Deflector
a
(degrees) / Velocity
(m/s) / Force
(N) / Deflector
a
(degrees) / Velocity
(m/s) / Force
(N) / Deflector
a
(degrees) / Velocity
(m/s) / Force
(N)
180 / 120 / 90

Part b

Deflector
a
(degrees) / Experimental
Slope / Calculated
Slope / Percent
error
180
120
90