One-Log Call Iterative Solution of the Colebrook Equation for Flow Friction Based on Pade Polynomials

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989100%3A27740%2F18%3A10240153" target="_blank" >RIV/61989100:27740/18:10240153 - isvavai.cz</a>

Result on the web

<a href="https://www.mdpi.com/1996-1073/11/7/1825" target="_blank" >https://www.mdpi.com/1996-1073/11/7/1825</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/en11071825" target="_blank" >10.3390/en11071825</a>

Result language

angličtina

Original language name

One-Log Call Iterative Solution of the Colebrook Equation for Flow Friction Based on Pade Polynomials

Original language description

The 80 year-old empirical Colebrook function zeta, widely used as an informal standard for hydraulic resistance, relates implicitly the unknown flow friction factor lambda, with the known Reynolds number Re and the known relative roughness of a pipe inner surface epsilon* ; lambda = zeta(Re, epsilon* ,lambda). It is based on logarithmic law in the form that captures the unknown flow friction factor l in a way that it cannot be extracted analytically. As an alternative to the explicit approximations or to the iterative procedures that require at least a few evaluations of computationally expensive logarithmic function or non-integer powers, this paper offers an accurate and computationally cheap iterative algorithm based on Pade polynomials with only one log-call in total for the whole procedure (expensive log-calls are substituted with Pade polynomials in each iteration with the exception of the first). The proposed modification is computationally less demanding compared with the standard approaches of engineering practice, but does not influence the accuracy or the number of iterations required to reach the final balanced solution.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10103 - Statistics and probability

Project

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Continuities

V - Vyzkumna aktivita podporovana z jinych verejnych zdroju

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Energies

ISSN

1996-1073

e-ISSN

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Volume of the periodical

11

Issue of the periodical within the volume

7

Country of publishing house

CH - SWITZERLAND

Number of pages

12

Pages from-to

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UT code for WoS article

000441830500209

EID of the result in the Scopus database

2-s2.0-85051172015