Research Article

Advanced Iterative Procedures for Solving the Implicit Colebrook Equation for Fluid Flow Friction

Table 10

Calculation of W(y) where y = Re/2.18 using the Newton–Raphson, the Halley, and the Schröder iterative methods.

Re = 5·106, y = Re/2.18 = 2293411.45Re = 3·104, y = Re/2.18 = 13760.47
Newton–RaphsonHalleySchröderNewton–RaphsonHalleySchröder

Iteration 0z0 = 15z0 = 15z0 = 15z0 = 15z0 = 15z0 = 15
Iteration 114.1063474913.2986055613.6820833814.0627630813.133339613.59610616
Iteration 213.2860494712.275734312.6255680213.1298653911.2917183812.20340124
Iteration 312.6286390512.1485578412.1773805712.202570639.52082916310.83006437
Iteration 412.25343232z = 12.1483570412.1483662811.283543028.0683234729.505729616
Iteration 512.1540775412.14835704z = 12.1483570410.379043357.5302668268.341483562
Iteration 612.1483746112.148357049.5045050147.5129302337.637280252
Iteration 7z = 12.148357048.697314341z = 7.5129296797.513654122
Iteration 812.148357048.0374562957.512929679z = 7.512929679
Iteration 97.6401057627.512929679
Iteration 107.52154464
Iteration 117.512971011
Iteration 127.51292968
Iteration 13z = 7.512929679
Iteration 147.512929679