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It depends on Reynolds number
and and inner pipe walls roughness LaTeX Math Inline body \rm Re
(see Fig. 1): LaTeX Math Inline body \epsilon
. LaTeX Math Inline body --uriencoded--f =f(%7B\rm Re%7D, \, \epsilon)
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[ Darcy friction factor Single-phase @model ] [ Darcy friction factor Multiphase Reynolds Number for Multiphase Flow @model ]
[ Moody Chart ] [ Reduced Friction Factor (Φ) ]
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