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## Main Question or Discussion Point

Hey all

I wasn't 100% sure whether to ask this in the general forums or the homework forums, it's more of a theory question rather than straight-up calculation question. If this is the wrong forum, please notify me and I'll repost this in the homework forum.

I've recently done a fluid mechanics laboratory where we measured the different head losses of oil in a pipe system, taking readings of head loss at 18 intervals. We did this test 5 times, varying the velocity at which the fluid travels, thus altering the Reynolds number.

A discussion question for this report is to discuss the development length of the fluid over the 5 tests.

My data leads me to the conclusion that turbulent flow (or namely, high Re flow), which has a lower overall darcy friction factor, has a significantly shorter development length than laminar flow.

Intuitively, I would say that the fluids development length would be greater when it's turbulent flow rather than laminar, seeing that turbulent flow would require more force?

I guess the question that I'm asking is, what do they specifically mean by development length in terms of turbulent flow? I imagine development length in terms of laminar flow would mean how much length would the flow need to stabilize itself into wholly laminar flow?

The formulas for theoretical development lengths are:

Laminar: L' = Re*0.06*Diameter(pipe)

Turbulent: L' = Re^(1/6)*4.4*Diameter(pipe)

Thanks for any help!

I wasn't 100% sure whether to ask this in the general forums or the homework forums, it's more of a theory question rather than straight-up calculation question. If this is the wrong forum, please notify me and I'll repost this in the homework forum.

I've recently done a fluid mechanics laboratory where we measured the different head losses of oil in a pipe system, taking readings of head loss at 18 intervals. We did this test 5 times, varying the velocity at which the fluid travels, thus altering the Reynolds number.

A discussion question for this report is to discuss the development length of the fluid over the 5 tests.

My data leads me to the conclusion that turbulent flow (or namely, high Re flow), which has a lower overall darcy friction factor, has a significantly shorter development length than laminar flow.

Intuitively, I would say that the fluids development length would be greater when it's turbulent flow rather than laminar, seeing that turbulent flow would require more force?

I guess the question that I'm asking is, what do they specifically mean by development length in terms of turbulent flow? I imagine development length in terms of laminar flow would mean how much length would the flow need to stabilize itself into wholly laminar flow?

The formulas for theoretical development lengths are:

Laminar: L' = Re*0.06*Diameter(pipe)

Turbulent: L' = Re^(1/6)*4.4*Diameter(pipe)

Thanks for any help!