An Integrated One-step Equation for Solving Duct/Pipe Friction Loss by Hand Calculator
American Journal of Mechanical and Industrial Engineering
Volume 4, Issue 2, March 2019, Pages: 28-34
Received: Jun. 18, 2019;
Accepted: Sep. 12, 2019;
Published: Sep. 26, 2019
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Chung-Yueh Ho, Tempace HVAC&R Consultancy Firm, Taiwan
Cheng-Ta Ho, Tempace HVAC&R Consultancy Firm, Taiwan
ASHRAE Handbooks are the worldwide reference books for HVAC engineers. When we tried to develop a duct software, we also followed the steps shown in 2013 ASHRAE Handbook. Accidently we found that some friction loss data of a duct design example seemed contrary to the data obtained from duct friction chart. Then we go back to adopt Darcy’s and Colebrook’s equations that have been used to solve duct/pipe friction loss for decades. However, the calculation process needs to use complicated computer program. After doing huge trial and error processes by computerized program, we obtained one integrated equation that can be used to calculate duct/pipe friction loss by hand calculator. We own an HVAC&R consultancy firm and have the opportunity to contact many real duct/pipe projects. This empirical equation has been successfully applied to dozens of actual duct and pipe design projects. For Reynolds Number (Re) is greater than 10,000 (i.e. turbulent flow), our analysis shows the friction losses obtained from this integrated equation are within ±2.0% of those obtained from Darcy’s and Colebrook’s equations. The accuracy (±2.0%) is good enough for engineers doing realistic duct/pipe designs. Hence, this one-step equation can be the handy alternative for Darcy’s and Colebrook’s equations. For the practical duct/pipe designs, engineers can calculate friction loss easily, no need to use iterative method.
An Integrated One-step Equation for Solving Duct/Pipe Friction Loss by Hand Calculator, American Journal of Mechanical and Industrial Engineering.
Vol. 4, No. 2,
2019, pp. 28-34.
Copyright © 2019 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/
) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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