# Fluid Mechanics - Estimating Reynolds number and flow rate.

## Homework Statement

A pipe 0.15m in diameter has a roughness ratio (k/d) of 0.002 and carries water at a flow rate Q.

Using the moody diagram, show that at high flow rates (where the friction factor is independent of reynolds number), the head loss per m length due to friction is approx 25.7(Q^2).

Estimate the lowest value of reynolds number and hence Q for which this result is valid.

## The Attempt at a Solution

I have already proved the first part of the question using the darcy-weisbach formula. But now I am unsure how to use that result in order to estimate the lowest value of reynolds number and flow rate. I know it involves reading from the moody diagram and I'm fairly sure it will be an iterative process, but I am stuck on how to actually go about it.

Any help would be really appreciated.

Thanks

EDIT:

If it helps the answers I have been given are

Re~ 6 x 10^5
Q~ 0.0807

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