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Peer Review

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(Already posted this to user talk page) Things that were done well:

  • I do like the information about how fanning friction factor relates to friction loss and pressure loss. It's great to see the application of the number and the importance. (but see below in improvements).
  • Providing the fanning friction factor for different geometries, flow regimes, and smooth vs. rough piping is very useful.

Things that could be improved:

  • I think some of the equations and math-heavy information in the lead section would be more appropriate in a different section. My understanding is this section is meant to be an informational overview. Perhaps a standalone applications section or something similar would be good.
  • Make sure to link to existing wikipedia articles. Ex: energy density (I need to do this too).

Clarefc (talk) 22:57, 27 February 2017 (UTC)[reply]

Peer Review

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There seems to be no spelling mistakes or issues with grammar. You did a really good job embedding equations and explaining their relevance and variables used in each equation. I think it would flow much better if you included more sections and subsections, also I think this article could use a picture. Continue citing your sources, there seems to be a lot of things that are not cited, and find more sources to strengthen your article. All in all, you did a good job, but there is lots of room to expand. Keep up the good work! Forbisl (talk) 22:30, 14 February 2017 (UTC) Logan Forbis[reply]

You are right about my citations. I am still working on this improvement. Huywilliam (talk) 06:22, 23 February 2017 (UTC)[reply]

Peer Review

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-Good job on order and flow.

-Equations were well explained and presented in an orderly fashion.

-Site source for first sentence and equation.

-Give definitions for variable of second equation (delta P) and site.

-Site Fanning Friction factor equation (delta h)

-Use Consistent formatting for Defining variables. Use the equation method for defining Re after the first friction factor equation.

-Make sure variables in equation match variable in key. For third friction factor equation it is T bar in equation but only T in definitions.

-Should the references come at the end of each sentence? Or is it ok in the middle of the sentence.

-Define variables right after Colebrook equation to maintain consistency. Llavecch (talk) 07:22, 16 February 2017 (UTC)[reply]


Thank you for pointing out those areas of improvement. I am still working on citations. I saw some articles use citations in the middle of the text but I will doublecheck it.Huywilliam (talk) 06:21, 23 February 2017 (UTC)[reply]

Wiki Education Foundation-supported course assignment

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This article is or was the subject of a Wiki Education Foundation-supported course assignment. Further details are available on the course page. Student editor(s): Huywilliam. Peer reviewers: Clarefc, Forbisl, Llavecch.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 21:10, 16 January 2022 (UTC)[reply]

Placement of factor 2

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http://en.wikipedia.org/w/index.php?title=Talk:Fanning_friction_factor&action=edit&section=1 I changed the equation to match the above source the two was on top when it would be on the bottom - 19:42, 3 April 2008 Orfintain

I reverted this change, since if I remember correctly, the formula with the Darcy (aka Moody) friction factor has the 2 on the bottom, while the formula with the Fanning friction factor has the 2 on the top. Bluap (talk) 19:58, 3 April 2008 (UTC)[reply]
The reversion agrees with a simplified version of the formula found here:
http://www.eng-tips.com/faqs.cfm?fid=1208
-Ac44ck (talk) 22:40, 3 April 2008 (UTC)[reply]

Factors 2 and g

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g in the denominator must be replaced by gc. gc is for the conversion unit for various system.For SI system of units gc is equal to 1.This details are as per the Mcabe and Smith's Unit Operation in Chemical Engineering.--Sakthi


Viscos friction head doesn't depend on acceleration due to gravity. g shall be removed from denominator and ρ (fluid density) placed in numerator.

Head does, indeed, depend upon the local acceleration of gravity. Refer to the simple version of the "manometer equation" in the example on page I-5 of this document:
http://www.cfdlab.ttu.edu/me3370/ChI.pdf
∆P = ρ g h
For a given pressure, the head will be higher on the moon (where there is less gravity) than the head on Earth.
I never liked the notion of g_c. If one pays attention to the units involved, it isn't needed. Realize that the lbf is defined using a mass unit of "slugs" and that 32.2 lbm = 1 slug, and all is well - no need for g_c, which is just a messy way of writing "1":
g_c = 32.2 ft lbm/(s^2 lbf) = 32.2 lbm/slug = 1
Perhaps g_c was an invention of pro-metric forces: dumb-down the users of English units (make them forget how the lbf is defined), introduce a complicating factor, and hope for the combination to exert pressure away from English units. -Ac44ck (talk) 03:43, 4 April 2008 (UTC)[reply]

The changes suggested above would convert the equation into an equation for pressure loss. For friction head, the "g" in the denominator is correct. I think that the "2" in the denominator is a mistake, however. Since the Fanning factor is 1/4 of the Darcy factor, the denominator in the friction head equation must be 1/4 of what it is in the Darcy equation. R is 1/4 of 2D. 2R is half of 2D.

The hydraulic radius of a pipe is 1/4 of its diameter. --Jagz 01:31, 15 March 2007 (UTC)[reply]

These are my suggestions: In order to have the friction head loss (hf) given with its correct dimension (metres, SI), the denominator would have to include the acceleration of gravity (g ~= 9,81 m / s^2 ). When using the hydraulic diameter approximation all one has to do is replace the D with 4Rh, keeping in mind that hydraulic diameter more often than not yields large variations in accuracy. JMJ 240707

g, not g_c

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I changed the formula to use 'g' instead of 'g_c'.

The units for this factor must be those of acceleration (L/T^2) if the 'head' is to have units of length.

g_c in the English system is 32.2 ft lbm/(s^2 lbf).

But 1 lbf = 1 slug-ft/s^2

So g_c ultimately has units of lbm/slug – a ratio of masses, which does not have units of acceleration. -Ac44ck (talk) 22:49, 3 April 2008 (UTC)[reply]

Darcy and Fanning Friction Factors

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The Wikipedia articles for Darcy and Fanning friction factors reflect the fourfold size ratio of Darcy over Fanning in the laminar region (Darcy f = 64/Re; Fanning f = 16/Re), but in the turbulent region exactly the same Colebrook equation is cited for both. This cannot be right.

Colin Braathen —Preceding unsigned comment added by 202.3.133.50 (talk) 22:36, 28 July 2010 (UTC)[reply]

I agree. This bugs me too. It is frustrating enough that there exists two different frictions (that differ only in multiples) and yet have identical definitions for both in each Wikipedia article. — Preceding unsigned comment added by 129.7.0.10 (talk) 01:23, 9 February 2017 (UTC)[reply]

"Evaluating Articles and Sources"

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1. The info came from printed sources, however, some of them are quite old, thus I feel like the references need to be updated. Unlike history, corrected formulas and newer knowledge will be added over time.

2. The article mentioned about the fanning factor for a round tube and a square tube. The formulas for tubes with other shapes should be mentioned as well as many kinds of tubes are used in industry (for example, triangular tube)

3. Head loss is mentioned in the article. Though it is relevant to the topic, the layout is not appropriate in my opinion. It should not be placed in the top part like this.

Huywilliam (talk) 03:14, 14 January 2017 (UTC)[reply]

I want to compile some useful sources for later use
1. Mohammad,, Khan, Kaleem. Fluid mechanics and machinery. ISBN 9780199456772. OCLC 927946607

2. Simons, Stefaan J.R.. (2007). Concepts of Chemical Engineering 4 Chemists - 3.6.1.1 Fanning Friction Factor. Royal Society of Chemistry. Online version available at: http://app-knovel-com.offcampus.lib.washington.edu/hotlink/pdf/id:kt00C4WXBO/concepts-chemical-engineering/fanning-friction-factor

3. Ellenberger, J. Phillip. (2014). Piping and Pipeline Calculations Manual - Construction, Design Fabrication and Examination (2nd Edition) - 4.5 Friction Factor. Elsevier. Online version available at: http://app-knovel-com.offcampus.lib.washington.edu/hotlink/pdf/id:kt00U13XV4/piping-pipeline-calculations/friction-factor

4. Chhabra, R.P. Richardson, J.F.. (2008). Non-Newtonian Flow and Applied Rheology - Engineering Applications (2nd Edition) - 3. Flow in Pipes and in Conduits of Non-Circular Cross-Sections. Elsevier. Online version available at: http://app-knovel-com.offcampus.lib.washington.edu/hotlink/pdf/id:kt006QSGS3/non-newtonian-flow-applied/flow-in-pipes-in-conduits

Huywilliam (talk) 05:42, 24 January 2017 (UTC)[reply]