Reynolds Number

Reynolds Number,
Re = (V.d1.ρ)/μ
Gives relation between density ρ, dynamic viscosity μ, and average velocity of fluid V in mass flow rates of fluid m, kg/s. From continuity equation, velocity V can be written:
v = (4m)/d­1.d1.ρ.π
By substituting V in equation Re = (V.d1.ρ)/μ, can be obtained :
Re = (4m)/d­1.μ.π