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Head loss at venturi meter

A venturi meter is being calibrated horizontally and has a diameter of 75mm at the entrance and 50mm at the throat . The flow rate is obtained by measuring the time required to collect certain amount of water . The average number of measurement gives 0.614m^3 of water in 55.82 second . If the pressure gauge at the inlet reads 20kN/ (m^2) more than the throat , calculate the head loss due to friction using Bernoulli's equation

how to do this ??
I think that if the pressure drop measured exceeds the pressure drop calculated due to the Bernoulli effect, you can say that the extra pressure drop has been caused by friction.
Reply 2
Original post by Smack
I think that if the pressure drop measured exceeds the pressure drop calculated due to the Bernoulli effect, you can say that the extra pressure drop has been caused by friction.

Do you have any idea how to do this question??

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Original post by wilson dang
Do you have any idea how to do this question??

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As per my post, work out the pressure drop due to Bernoulli and if it is smaller than the measured pressure drop, then the extra pressure drop can be assumed to have been caused by friction.
Reply 4
Original post by Smack
As per my post, work out the pressure drop due to Bernoulli and if it is smaller than the measured pressure drop, then the extra pressure drop can be assumed to have been caused by friction.

How to work out pressure drop due to bernoulli??

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Reply 5
Original post by wilson dang
How to work out pressure drop due to bernoulli??

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How to know the measured pressure drop ?

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Original post by wilson dang
How to know the measured pressure drop ?

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It tells you in the question.
Reply 7
Original post by Smack
It tells you in the question.

Do you mean this????
Original post by wilson dang
Do you mean this????


Can you rotate it so I can read it?
Reply 9
Original post by Smack
Can you rotate it so I can read it?


can read now ?
Original post by wilson dang
can read now ?


That looks okay to me I think. I kinda forgot how to integrate head loss due to friction in the Bernoulli equation (been too many years since I've done this kind of stuff) so my method would have been more complicated actually.
anyone can comment on my answer ?

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