Cyclohexane is used as the solvent in a process. In part of the process, cyclohexane flows throught a L = 10m straight pipe (NPS 3 inch, SCH40, see Slide-6) at T 70C. The dyanmic viscosity can be calcualted using the following correlation (application temperature range: 280-553K): B A = A expe+ C-T +DT2) T (1) For cyclohexane, the parameters are: A=1.23 x 10-5, B = 1380.0, C = -1.55 x 10-3, D = 1.157 x 10-6 Units: T(K), : (Pa.) The density of cyclohexane at the process temperature is p=0.776 g/ml. There are two flow rates can be used in this process design: F = 0.66 GPM and Fs = 13 GPM (1). calculate the Reynolds numbers for these two flow rates and determine the flow types for these two flow rates. (10pt) (2) Darey-Weisbach function and Moody diagram (see slide-10 used in the class) provide a fast estimation of pressure drop. Darcy-Weisbach equation is shown below: I po? (2) AP = ID 2 in which AP is pressure drop (unit: Pa), L is the pipe length (unitim), D is the pipe diameter(unit:m), p is the liquid density (kg/m) and is the linear flow velocity (unit: m/s). S is the friction factor which can be read from Moody dingram. For laminar flow (Re 1000), / depends on both Re and relative roughness(e/D) (y-axis on the right). If the pipe relative roughness e/D = 0.002, calculate the pressure drop (unit:Pa) using Moody-dingram and Darcy Weisbach equation for these two flow rates. 10pt) Moody Diagram 2 Cru 0.1 0.00 100 0.07 0.08 0.00 0.04 0.00 EN 0.05 0.015 0.01 law 0.04 00 0.005 2000 Low . LpV 0.02 0.001 10000 = f. D2 0.000 0.0001 50 001 20 08 10 10