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Q: pipeing flow loss ( Answered ,   1 Comment ) Question
 Subject: pipeing flow loss Category: Miscellaneous Asked by: hutch03-ga List Price: \$2.00 Posted: 04 Aug 2005 06:35 PDT Expires: 03 Sep 2005 06:35 PDT Question ID: 551594
 ```formula for estimating flow loss in pipeing installations due to fittings such as elbows``` Subject: Re: pipeing flow loss Answered By: landog-ga on 04 Aug 2005 08:37 PDT Rated: ```Hi, Thanks for the question. I believe you are looking for something utilizing The Darcy equation/law. "Darcy's Law is a phenomologically derived constituative equation that describes the flow of a fluid through a porous medium (typically water through an aquifer). The law was formulated by Henry Darcy based on the results of 1855 and 1856 experiments on the flow of water through beds of sand. It, along with the conservation of mass, comprises the groundwater flow equation, which is one the basic building relationships of hydrogeology." http://www.answers.com/topic/darcy-s-law This equation may help you: hL = f(L/D)v2/2g hL - pressure f - friction factor L/D - the ratio of pipe length to internal diameter v - velocity of flow g - the acceleration of gravity Fittings and valves & bends also affect the pressure drop. The above equation requires a modification: hL =K v2/2g K is the resistance coefficient, which is defined as the number of velocity heads (or pressure) lost due to the valve or fitting. If desired, one can relate this resistance coefficient to equivalent pipe length by using the Darcy equation: K = f(L/D) f is the friction factor and L and D are the length and diameter of the pipe, in feet. Fitting K coefficient ====================================== 90 degree Mitre(elbow) 60f 90 degree Sweep 30f 45 degree sweep 10f More details can be found here: http://www.procooling.com/articles/html/maximizing_flow_rates_with_h2o.php Crane Technical Paper No. 410 (TP-410) is the ultimate guide to understanding the flow of fluid through valves, pipe and fittings, assisting you to select the correct equipment for your piping system: http://www.cranevalve.com/tech.htm A very nice document that details other factors that affect flow rates through pipes (velocity, friction, viscosity and density: http://www.rosemount.com/document/pds/flowfund.pdf```
 hutch03-ga rated this answer: ```Wow that was fast,the equation or law that you quoted apears to be over my head but I may be able to muddle through thanks``` `Please let me know if you need help.` 