Equal friction method for duct sizing

  • #1

Homework Statement


In the attachment.

Homework Equations


Chart of pressure loss due to friction for steel ducts : http://postimg.org/image/4iml9x761/

The Attempt at a Solution


I dont understand the deltaP/L column of the results table.
Where did the values come from? Shouldn't they all be 0.063 in.wg / 100ft or 0.5 Pa/m since the principle of the equal friction method is to have the same pressure loss per length for the entire system?
 

Attachments

  • equal friction method.docx
    2.4 MB · Views: 108

Answers and Replies

  • #2
gneill
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Hi pinkcashmere. I don't know if others have the same difficulty, but I can't see anything in your docx attachment. Can you grab some relevant images (perhaps with a snipping tool) and upload them so they are visible in the thread? You will get better results here at PF if helpers don't have to download files from offsite and they can see the problem without having to click through to images.
 
  • #3
SteamKing
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Hi pinkcashmere. I don't know if others have the same difficulty, but I can't see anything in your docx attachment. Can you grab some relevant images (perhaps with a snipping tool) and upload them so they are visible in the thread? You will get better results here at PF if helpers don't have to download files from offsite and they can see the problem without having to click through to images.

Hi gneill,
I printed out the Word document pinkcashmere posted as an Acrobat file, which is attached below.
 

Attachments

  • EqualFriction.pdf
    170.8 KB · Views: 177
  • #4
gneill
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Hi gneill,
I printed out the Word document pinkcashmere posted as an Acrobat file, which is attached below.
Thanks. Wow! 2.4 MB docx file becomes a 171 KB pdf, and it boils down to a half page of text. I have seen the end of civilization, and it is a result of bloatware :smile::smile::smile:

edit: okay, I didn't page down. A page and a half of text o_O
 
  • #5
SteamKing
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Thanks. Wow! 2.4 MB docx file becomes a 171 KB pdf, and it boils down to a half page of text. I have seen the end of civilization, and it is a result of bloatware :smile::smile::smile:
The reason the .docx file was so huge, I believe, was that it consisted of several pages scanned from a text book. Those image files are generally dumped into the .docx file with no compression.
 
  • #6
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I dont understand the deltaP/L column of the results table.
Is not this column for straight pipe only (not equivalent length)?
 

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