A followup on Lusk-Darcy friction factors

[HarveyHensley]

Fred Lusk posted documents that evaluate the many formulas that can be used to obtain the Darcy friction factor explicitly. In the subsequent discussion, I proposed ranking the formulas in a different manner. However, my suggested change did not greatly change the ranking. Also, I have been able to locate some experimental data on commercial pipes operating in the transition region and found that the Colebrook-White formula does perform well for that region also.

Fred has asked to see my results which are attached to this discussion.

Fred, my modifications have messed up the page breaks and I haven't taken the time to make the file more presentable.

I plan on posting my evaluation of the CW formula against the Freeman data on my website blog soon. http://www.harveyhensley.com/ It will be a minor contribution compared to your document.

Update 6/1/2014: The blog mentioned above has been posted.

[MikeArmstrong]

Nice work Harvey

[HarveyHensley]

Please note that the rankings in my file attached to the original discussion are Fred's rankings based on S4. I ranked them by hand based on my new statistics and found that the rankings didn't change significantly. Thus, I didn't change the rankings in the update of Fred's document.

[FredLusk]

Harvey…

I apologize for being incommuncado for several weeks. I've been out-of-town quite a bit lately and just haven't had time to get back to this…except for plodding along timing the functions which is now almost complete. I downloaded your file and will be looking at it this week (I hope).

Fred

(P.S. this is a duplicate comment to the one I left on the comment thread for my original documents.)