[amp_mcq option1=”Width of the throat should not be less than one-third of the bed width of main canal” option2=”Length of the throat should be 2.5 times the depth measured to F.S.L. in the main canal” option3=”Minimum throat width should not be less than 60 cm” option4=”All the above” correct=”option4″]
The correct answer is D. All the above.
The width of the throat should not be less than one-third of the bed width of main canal. This is to ensure that the flow through the venturi meter is uniform. If the width of the throat is too small, the flow will be turbulent and the head loss will be greater.
The length of the throat should be 2.5 times the depth measured to F.S.L. in the main canal. This is to ensure that the pressure drop across the venturi meter is sufficient to measure the flow rate accurately. If the length of the throat is too short, the pressure drop will be too small and the flow rate will be underestimated.
The minimum throat width should not be less than 60 cm. This is to ensure that the venturi meter is able to handle the maximum flow rate that is expected. If the throat width is too small, the venturi meter will be choked and the flow rate will be underestimated.
In addition to the above, the following should also be considered when designing a venturi head:
- The material of the venturi head should be corrosion-resistant.
- The venturi head should be installed in a straight section of the canal.
- The venturi head should be properly aligned with the flow.
- The venturi head should be properly sealed to prevent leakage.