The relationship between the friction factor and Reynolds number for laminar flow in pipes is a fundamental result of fluid dynamics, established by the Hagen-Poiseuille equation.
It is usual to designate the frictional resistance to flow in a pipe by Darcy-Weisbach equation: $h_{f} = \frac{4fLV^{2}}{2gd}$ For laminar viscous flow (Re < 2000) through a circular pipe, the friction factor 'f' varies inversely with Reynolds number (Re) as : - (5) Question not attempted
Asked in Assistant Eng. (Mechanical) Competitive Examination, 2023 · Topic: Mechanics (Fluid Statics and Dynamics (Continuity Equation, Bernoulli's Theorem))
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