Difference between revisions of "Colebrook-White Equation"

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(Created page with "[1] The governing equation used to calculate the expected friction loss factor (f) used in the Darcy-Weisbach Equation. The equation is a function of pipe surface roughness, p...")
 
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The frictional head loss gradient, <math>i_F</math>, can be determined from the '''Colebrook-White equation''', which for pipes flowing 100% full of water may be written in the form;
 
The frictional head loss gradient, <math>i_F</math>, can be determined from the '''Colebrook-White equation''', which for pipes flowing 100% full of water may be written in the form;
  <math>i_F = ( \frac{u^2}{8gd_1} )</math>
+
  <math>i_F = ( \frac{u^2}{8gd_1} ) { \Big\{ {log_{10}} [ \frac{k_p}{371d_1} + \frac{1.775v} {\sqrt{gi_F d_i}^3} ]}^{-2}</math>
i_"F " =(u^2/(8gd_1 )) {log_10⁡[k_p/(3710d_1 )+1.775"v" /√(gi_"F"  d_i^( 3) )] }^(-2)
 
  
  
  NOTE: An iterative method of solution is required to find the head loss gradient, i_"F " , from equation because this quantity also appears on the right-hand side of the equation.
+
  NOTE: An iterative method of solution is required to find the head loss gradient, <math>i_F</math>, from equation because this quantity also appears on the right-hand side of the equation.

Revision as of 17:02, 8 September 2017

[1] The governing equation used to calculate the expected friction loss factor (f) used in the Darcy-Weisbach Equation. The equation is a function of pipe surface roughness, pipe diameter, fluid viscosity and fluid velocity.

[2] The loss of energy head, \Delta h_F, due to wall friction in a length of pipe between points 1 and 2 in a system is given by:

\Delta h_F = i_FL_p 

The frictional head loss gradient, i_F, can be determined from the Colebrook-White equation, which for pipes flowing 100% full of water may be written in the form;

i_F = ( \frac{u^2}{8gd_1} ) { \Big\{ {log_{10}} [ \frac{k_p}{371d_1} + \frac{1.775v} {\sqrt{gi_F d_i}^3} ]}^{-2}


NOTE: An iterative method of solution is required to find the head loss gradient, i_F, from equation because this quantity also appears on the right-hand side of the equation.