Pipe sizing of district cooling distribution network using implicit Colebrook-White equation
An implicit solution of Colebrook-White equation was used in calculating the friction factor for commercial steel pipes using Newton-Raphson method with Reynolds number ranging from 4.0×103 to 1.3×107. Initial value for iterative friction factor estimation was based on expanded form of Colebrook-Whi...
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| Main Authors: | , , |
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| Format: | text |
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Animo Repository
2016
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| Online Access: | https://animorepository.dlsu.edu.ph/faculty_research/2795 |
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| Institution: | De La Salle University |
| Summary: | An implicit solution of Colebrook-White equation was used in calculating the friction factor for commercial steel pipes using Newton-Raphson method with Reynolds number ranging from 4.0×103 to 1.3×107. Initial value for iterative friction factor estimation was based on expanded form of Colebrook-White equation for larger values of Reynolds number with tolerance value of 1.0×10-8. Numerical results were compared with known explicit solutions and iterative procedure proposed by Lester in which, their mean difference, root-mean square deviation, mean relative error and correlation coefficient were evaluated. Correlation coefficients equal to unity and overall mean relative error of 4.821×10-8 were achieved for all fifteen (15) pipe cases with nominal diameters ranging from 100mmto 1,500mmwhen compared with iterative solution suggested by Lester. Student's t-test for paired data was also used which yielded a calculated t-value of -5.406×10-4. Combining the piping network design criteria with the logical structure of friction factor calculation determines the pipe size of distribution network and defines the boundaries of chilled-water velocities at different pressure drop limits as a function of commercial steel pipe diameter according to ANSI B36.1. |
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