6.154 Water at 20°C flows through the orifice in the figure, which is monitored by a mercury manometer. If d = 3 cm, (a) what is h when the flow is 20 m'/h; and (b) what is Q when h= 58 cm? 3 ст, %3D water d-3 cm D=5 cm Solution: (a) Evaluate V = Q/A= 2.83 m/s and Rep = pVD/µ = 141,000, B= 0.6, thus Ca 0.613. mercury Fig. P6.154

In assignment 3 I gave you the following expression for the pressure drop for turbulent flow through a horizontal smooth pipe of constant diameter at the special condition to which the Blasius equations applies: 0.25 L 0.75 1.75 AP = 0.241. BONUS Derive this equation. μ D4.75

Show complete solution.

1) Pavithran Ravindran explains to a group of inspiring CBE students that the Reynolds number is a dimensionless group defined for a fluid flowing in a pipe as Re = Dvp/µ where D = pipe diameter, v = average fluid velocity, p = fluid density, and u = fluid viscosity. When the value of the Reynolds number is less than about 2100, the flow is laminar -- the fluid flows in smooth streamlines. For Reynolds numbers above 2100, flow is turbulent -- a great deal of internal agitation takes place. %3D Methyl ethyl ketone (MEK) flows through a 2.067-in. ID pipe at 20°C, at which temperature its density is 0.805 g/cm³ and its viscosity is 0.43 centipoise (1 centipoise = 1.00 x 10-3 kg/m.s). The average fluid velocity is 0.048 ft/s. Determine whether the flow is laminar or turbulent. %3D