# Parallel pipeline flow rate

#### doskdan

Hello to everybody,

The problem is given here:

My diagram is here:

Per problem question, do we need to find Q2 and Q3 which is governed by Q1=Q2+Q3?

I am also stuck with the absence of data for viscosity and diameter. How to manage them?

Can we express the equation given in the problem in terms of heads?

Thanks

Last edited:

#### ChipB

PHF Helper
You can determine a value for $$\displaystyle \frac {d^4}{\mu}$$ from the intial data of Q, L, and $$\displaystyle \Delta p$$. Then after the 2nd pipe is added you have:

$$\displaystyle Q = \frac {\pi d^4 (\Delta P_1)}{128 \mu (12.8\ Km)} = 2 \frac {\pi d^4 (\Delta P_2)}{128 \mu (19.2\ Km)}$$

Combine this with $$\displaystyle \Delta P_1 + \Delta P_2 = 34\ bar$$

and you can solve for Q.

#### doskdan

You can determine a value for $$\displaystyle \frac {d^4}{\mu}$$ from the intial data of Q, L, and $$\displaystyle \Delta p$$. Then after the 2nd pipe is added you have:

$$\displaystyle Q = \frac {\pi d^4 (\Delta P_1)}{128 \mu (12.8\ Km)} = 2 \frac {\pi d^4 (\Delta P_2)}{128 \mu (19.2\ Km)}$$

Combine this with $$\displaystyle \Delta P_1 + \Delta P_2 = 34\ bar$$

and you can solve for Q.
Thanks a lot for your help.