  Using only a limited number of computationally expensive functions, we show a
way how to construct accurate and computationally efficient approximations of
the Colebrook equation for flow friction. The presented approximations are
based on the asymptotic series expansion of the Wright Omega-function and
symbolic regression. The results are verified with 8 million of Quasi-Monte
Carlo points covering the domain of interest for engineers. In comparison with
the built-in wrightOmega feature of Matlab R2016a, the herein introduced
related approximations of the Wright Omega-function significantly accelerate
the computation. With only two logarithms and several basic arithmetic
operations used, the presented approximations are not only computationally
efficient but also extremely accurate. The maximal relative error of the most
promising approximation which is given in the form suitable for engineers use
is limited to 0.0012%, while for a little bit more complex variant is limited
to 0.000024%.
