Chapter 10B

10 B. Pipe Diameter using Equations 10.19 and 10.20 Back to Main

This page is used to determine the inside line diameter (d) needed for a given flow rate and pressure drop. The friction factor, f, and Reynolds number, Re, are a function of diameter and velocity terms. Therefore, the use of the correlation of f plotted against Re involves a trial and error solution if diameter is desired. A direct solution for diameter is possible by algebraic manipulation of the basic equations.

Solving for "d" yields

For small pipe, (10.19)

For large pipe, (10.20)

Where: d = diameter

q = volumetric flow rate

r = density

m = viscosity

L = length of line

= mass/force conversion constant

= Frictional pressure drop

The units are defined as those listed on page 321. To carry out the inside diameter calculation the Liquid viscosity, Liquid density, Pipe length, Flow rate, and Friction pressure loss of the fluid must be entered into their entry space. To do so use the mouse to click the curser in their entry space and input the data. Once this has been done, select Run to execute the solution.

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