Concept explainers
Water enters a two-armed lawn sprinkler along the vertical axis at a rate of 75 L s. and leaves the sprinkler nozzles as 2-cm diameter jets at an angle of
(a)
The rate of rotation of sprinkler.
Answer to Problem 89P
The rate of rotation of the sprinkler is
Explanation of Solution
Given information:
Length of sprinkler arm is
Write the expression for the area of outlet of jet.
Here, the diameter of jet is
Write the expression for outlet velocity.
Here, the volume flow rate is
Write the expression for the radial velocity
Here, the jet velocity is
Substitute
Write the expression for jet velocity.
Write the expression for the angular momentum about axis of rotation.
Here, the length of arm of sprinkler is
Write the expression for rate of rotation of impellor.
Here, the angular velocity is
Substitute
Substitute
Substitute
Substitute
Substitute
Conclusion:
The rate of rotation of the sprinkler is
(b)
The rate of rotation of sprinkler.
Answer to Problem 89P
The rate of rotation of the sprinkler is
Explanation of Solution
Given information:
The vane angle is
Substitute
Substitute
Substitute
Substitute
Substitute
Conclusion:
The rate of rotation of the sprinkler is
(c)
The rate of rotation of sprinkler.
Answer to Problem 89P
The rate of rotation of the sprinkler is
Explanation of Solution
Given information:
The vane angle is
Substitute
Substitute
Substitute
Substitute
Substitute
Conclusion:
The rate of rotation of the sprinkler is
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Chapter 6 Solutions
Fluid Mechanics: Fundamentals and Applications
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