Comment on “Gene expression programming analysis of implicit Colebrook–White equation in turbulent flow friction factor calculation”

Recently, it is investigated (Samadianfard, 2012) the potential of genetic programming based technique in estimating flow friction factor in comparison with the most currently available explicit alternatives to the Colebrookʹs equation. iterative solution of the Colebrookʹs equation which is accurate to six significant digits, this discussion showed that the proposed approximation by the author for friction factor is not very accurate (the errors increase up to 7.374%), thus it is proposed two new accurate approximations (with maximum error less than 0.022% and 0.008%) for estimating flow friction factor.