I am trying to calculate the flow rate out of a generic Y shaped pipe system. I am given the area and velocity of the first pipe, as well as the areas and percentage of flow into the 2nd & 3rd pipes (from the 1st pipe). I am supposed to find the discharge out of pipes 1,2, & 3, as well as the mean velocities in pipes 2 & 3.


My theoretical question: It also asks to repeat the calculation process using blood as the fluid instead of water, and I am wondering if the change in density will actually trigger any changes in the flow rates/velocities i need to calculate?

Here was my process: I found the flow out of pipe 1 (Q = Velocity x Area), and used this value to find the flows in pipes 2 & 3 based off of percentages given in question. Next, I used the flows in 2 & 3 to find the velocities in each pipe. None of this seemed to required knowledge of fluid density.

Am I doing something wrong?



This post was edited by DeVaginey on Apr 3 2015 04:52pm

The density change shouldn't change the volume flow rate, at least in the context of the question. I would be more concerned with viscosity but they dont even talk about it so I guess it would just be an increase in what, 6%? If you assume that you have the same mass flow then it would change everything but they dont really ask you to do that. It is strange I agree.

thank you for the clarification! I have been wondering about this for a few hours haha