×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Cameron versus Crane Technical Paper #410

Cameron versus Crane Technical Paper #410

Cameron versus Crane Technical Paper #410

(OP)
It seems to me that most of the loss information contained in Cameron Hydraulic Data manual is derived from Crane's Technical Paper #410:  Flow of Fluids through Valves, Fittings, and Pipe.  For example, the table on page 3-120 of Cameron uses the K-values from Technical Paper #410 with a friction factor assumed.

One issue of confusion, in Cameron (on page 3-118) they show the K-value for gradual enlargements as:

K = (1 - (D1^2/D2^2))^2

Technical Paper #410 uses the following formula (see page A-26, Formula 4):

K = (1 - (D1^2/D2^2))^2/(D1/D2)^4

The denominator in the Crane's formula makes the K-value almost an order of magnitude difference in some cases.  

For example, for a sudden enlargement from a 16" pipe to 24" pipe, the K value according to Cameron is 0.3 while the K value according to Crane is 1.5.

Does anyone know which is correct or if both of them are correct?  My opinion is that Crane is correct and Cameron is wrong (since Cameron borders on plagiarizing Crane), but you would think by 19th edition of Cameron, they would have this corrected.  Any ideas?

Thanks,
M

RE: Cameron versus Crane Technical Paper #410

Both are correct, just on a different basis. The K value from Cameron is based on the smaller diameter, while the Crane expression is based on the larger diameter. The Crane reference you gave (page A-26 Formula 4) shows that to express it as K1 you just multiply K2 by B4. (Subscripts 1 and 2 refer to the smaller and larger diameters respectively.)

Harvey

Katmar Software
Engineering & Risk Analysis Software
http://katmarsoftware.com

RE: Cameron versus Crane Technical Paper #410

(OP)
D'OH!  

Now that you point that out, I realized something I was overlooking.  On page 3-4 of Crane is the note:

"The values of the resistance coefficients (K) in equations 3-17, 3-18, and 3-18.1 are based on the velocity in the small pipe.  To determine K values in terms of the greater diameter, divide the equations by B^4."

Also, Equations 3-17.1 and 3-18.1 from Crane are the same equations from Cameron (#2 and #4 on page 3-118).

Time to change my spreadsheets!

Thanks for the clarification,
M

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources