Do you need to increase pressure to pump a fluid from a large pipe through a small pipe? The appli

Jay Barrett 2022-05-13 Answered
Do you need to increase pressure to pump a fluid from a large pipe through a small pipe?
The application of this question is towards clogged arteries and blood flow. I am wondering why people with clogged arteries have high blood pressure if a smaller artery (assuming it is smooth and cylindrical) means less pressure exerted by the blood according to Bernoulli's Equation. Is this because the heart has to pump the blood harder to be able to travel through a smaller arterial volume?
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Answers (2)

TettetoxDetnhte5
Answered 2022-05-14 Author has 15 answers
I am not sure if the same laws apply to the heart as that of mechanical pump, but for a given flow rate, say X gallons per minute, the mechanical pump must develop a pressure P to overcome pipe friction and any other force trying to retard flow. If the pipe in a system is reduced in size, to pump the same flow rate a higher pressure will be required. The higher pressure will also require an increase in horsepower.
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Jazlyn Raymond
Answered 2022-05-15 Author has 1 answers
The Bernoulli equation is a good approximation only if viscous flow resistance is not important. In blood flow through arteries, veins and (particularly) capillaries, viscous flow resistance is very important.
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