A solution is pumped through a 5cm diameter stainless steel

A solution is pumped through a 5cm diameter stainless steel pump. The solution has a density of 1,050 kg/m³ and a viscosity of 995 x 10^-6 Pas. Please calculate the minimum flow rate that will ensure turbulent flow.

Solution

the reynolds number: Re >4000

so,    pVD/u = 4000

       (1050)V(0.05)/(995*10^-6) = 4000

    V = 0.0758 m/s

hence, the flow rate is,

   Q = AV = [pi*d^2/4]*V = 0.000148 m^3/s