Q = Volume flow rate, = find, P= find E, the velocity of approach factor, can be calculated with E = 1 / sqrt(1-B^4) E = 1 1-B4 requires knowledge of the product CE. The beta ratio is = do/d1 Then, the Reynolds number needs to be calculated: Red1 4Q Where, v is the fluid kinematic viscosity And d1 is the circular pipes diameter. PROBLEM 2: Determine the size of an orifice plate to meter the steady flow of water at 20 C flowing through a 38-cm pipe if the nominal flow rate expected is 200 kg/s and the pressure drop must not exceed 17.3 kPa. The upstream pressure is 101.3 kPa abs.