What effect does pipe diameter have on resistance to turbulent air flow?

Answer 1

You are interested in finding out the details of the Reynolds Number.

This quanity for various flow geometies (pipes, etc) will show when the turbulent flow is happening for various values of the Reynolds number. Its been awhile so I don't remember exactly what the hard number is but if you look at the equation of how Re is defined (look at the source link), you'll see the Re is proportional to the characteristic length.

Answer 2

A pipe of very large diameter would have constant turbulence even at low flow velocities.

It follows that a small diameter pipe should produce little or no turbulence.

However, the frictional resistance of the pipe wall would have to be low to maintain laminar flow.The flow velocity is another limiting factor.

Small diameter tubing is used in the manufacture of pneumatic switching devices e.g. AND, OR, NOT, NOR, NAND gates.

Unless the tubing supported lamina flow then the COANDA effect, enabling these devices to work efficiently, would not operate.

Answer 3

Constant inside pipe diameter will make the turbulent flow to be more laminar after some distance. Also, pipe inside diameter has to be smooth and not rough.

Answer 4

pipe diameter is crutial, however turbulent flow will go at arounf 15 pipe diameters down stream of the source of the turbulence ( usually a sharp bend) you need to check out Bernoullis equation

Answer 5

increasing pipe diameter- increases turbulent flow

Answer 6

Regardless of the type of flow, the friction loss increases rapidly as the diameter decreases. Your resistance is directly proportional to the friction loss.

Answer 7

pipe diameter determines the velocityo of airflow thrrough the pipe and the fluid resistance is calculated based on the velocity,rougness of the pipe, viscosity of air, temperature of air etc.

Answer 8

Surely the air speed and pressure also need to taken into account?