In the complete turbulence zone (in rough pipes), the (A) Rough and smooth pipes have the same friction factor (B) Laminar film covers the roughness projections (C) Friction factor depends upon NRe only (D) Friction factor is independent of the relative roughness

In the complete turbulence zone (in rough pipes), the
(A) Rough and smooth pipes have the same friction factor
(B) Laminar film covers the roughness projections
(C) Friction factor depends upon NRe only
(D) Friction factor is independent of the relative roughness
by

1 Answer

Answer :

(D) Friction factor is independent of the relative roughness
by

Related questions

In turbulent flow, a rough pipe has the same friction factor as a smooth pipe (A) In the zone of complete turbulence (B) When the roughness projections are much smaller than the thickness of the laminar film (C) Everywhere in the transition zone (D) When the friction factor is independent of the Reynold's number

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Last Answer : (B) When the roughness projections are much smaller than the thickness of the laminar film

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Friction factor for a hydraulically smooth pipe at NRe = 2100 is f1 . If the pipe is further smoothened (i.e., roughness is reduced), the friction factor at the same value of NRe , will (A) Increase (B) Decrease (C) Remain unchanged (D) Increase or decrease depending on the pipe material

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