0
$\begingroup$

When I have a pipe (1) that branched into 2 pipes (2 and 3). I noticed that Bernoulli's equation can be applied between point 1 and 2 or 1 and 3. So my question is how is this valid? Isn't Bernoulli just an energy balance so the energy at point 1 in the the original pipe should be equal to the sum of energies at point 2 and 3? I tried starting with this equation and dividing by the mass flow rate at each point (taking into consideration the continuity equation) and ended up with this $$\dot{m_2}e_1+\dot{m_3}e_1 = \dot{m_2}e_2+\dot{m_3}e_3 $$where e is the energy per mass passing in the pipe per second. But this doesn't strictly imply that $e_1 = e_2$ or $e_1 = e_3$.

Also can Bernoulli's equation be applied on points 2 and 3 (between the 2 branched pipes)?

$\endgroup$
3
  • $\begingroup$ Could you spell check the name? $\endgroup$
    – my2cts
    Commented Nov 13, 2019 at 0:51
  • $\begingroup$ But the equation is consistent with the latter two conditions. You can apply the Bernoulli equation separately to the portion of the flow between points 1 and 2 and to the portion of the flow between points 1 and 3. It is not valid to apply the Bernoulli equation to points 2 and 3, because the represent different flows. $\endgroup$ Commented Nov 15, 2019 at 15:38
  • $\begingroup$ Okay, but why is it possible to apply Bernoulli's principle after the flow separates into 2? Am I mistaken about Bernoulli's principle being an energy balance? $\endgroup$
    – Peter
    Commented Nov 18, 2019 at 14:32

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.