How to calculate header pipe length

  • Thread starter Thread starter SpencerC
  • Start date Start date
  • Tags Tags
    Length Pipe
AI Thread Summary
Calculating header pipe length for an equal length design involves understanding the friction losses associated with various bends in the piping, such as 45, 60, 90, and 180 degrees. While equal centerline length is straightforward, achieving equal losses may be more complex, as equal volumes can be more critical. The pressure drop in a header pipe is minimal compared to the cylinder pressure during exhaust valve opening, making pressure wave dynamics essential in header design. Reliable resources for this information include textbooks on automotive tuning and computational fluid dynamics, though commercial software can be costly. Overall, thorough research and testing are vital for effective header design.
SpencerC
Messages
2
Reaction score
0
Hey guys n gals, Looking for a little help here. I am looking to build an equal length header for my truck and was wondering how to calculate the losses through the amount of 45, 60, 90 and 180deg bends for 1.5 sch.40 pipe. Now, for clarity, I do NOT mean equal centerline length, that's easy enough.

In the picture is an idea of what I am talking about. From right to left the first pipe would seem to have less friction loss than 3 or 4.

Explain it all, This curious mind likes to learn :) Thanks in advance.
 

Attachments

  • cummins5.jpg
    cummins5.jpg
    50.2 KB · Views: 958
Engineering news on Phys.org
There have GOT to be standard tables for such losses...engineers must use that kind of stuff all the time...
 
I'm not so sure that the equal length approach is intended to give equal losses, it may be more important that the volumes be equal.

Just to make up a few numbers, a header pipe exhausting a one-liter cylinder running at 5000 rpm is going to pass about 80 cubic foot per minute (for a four stroke). If this pipe is about two feet long the pressure drop in the pipe is only a fraction of a psi (about 0.2). This is small relative to the pressure in the cylinder when the exhaust valve opens.

Header design is all about the pressure waves or pulses which take place due to the periodic stroking of the exhaust valve. There are a number of excellent textbooks out there that go into this in great detail. Commercial software such as that identified above is typically based on steady-flow solutions which are of no help in this instance. Headers are designed using (1) well established thumbrules,(2) extensive testing, and (3) maybe some sophisticated computational fluid dynamics (CFD). The price tag on those kinds of programs make the 700 GbPound price of the steady state piping program look cheeep.

Check Amazon dot com for automotive books with "tuning" in the title. A Graham Bell's books are classics, but there are many others.
 
gmax137 said:
Check Amazon dot com for automotive books with "tuning" in the title. A Graham Bell's books are classics...

seconded
 
Thanks a lot for the info guys. That really helped a lot.
 

Thread 'Questions about the Tesla turbine'

Hi all, i have some questions about the tesla turbine: is a tesla turbine more efficient than a steam engine or a stirling engine ? about the discs of the tesla turbine warping because of the high speed rotations; does running the engine on a lower speed solve that or will the discs warp anyway after time ? what is the difference in efficiency between the tesla turbine running at high speed and running it at a lower speed ( as fast as possible but low enough to not warp de discs) and: i...
View full post »
Thread 'Where is my curb stop?'

Thread 'Where is my curb stop?'

My water meter is submerged under water for about 95% of the year. Today I took a photograph of the inside of my water meter box because today is one of the rare days that my water meter is not submerged in water. Here is the photograph that I took of my water meter with the cover on: Here is a photograph I took of my water meter with the cover off: I edited the photograph to draw a red circle around a knob on my water meter. Is that knob that I drew a red circle around my meter...
View full post »

Similar threads

Hydraulic Losses Through a Pipe
Replies
1
Views
2K
How can I find the cleanout for my building drain?
2
Replies
59
Views
621
Calculating Heat Loss in Pipes with Air Flow and Water Surrounding
Replies
15
Views
5K
Calculate Heat Loss from Pipes: Tips & Example Calculation
Replies
6
Views
11K
[Fluid Dynamics] Losses in branched pipes etc.
Replies
2
Views
2K
How can I calculate heat loss in a hot water pipe system?
Replies
1
Views
4K
Calculating bending stress on a pipe
Replies
3
Views
5K
Layer of Ice in water pipe (affect on heat transfer)
Replies
10
Views
6K
How do you calculate flowrate exiting a pipe?
Replies
2
Views
8K
Pressure drop analysis on water pipe system w/pump
Replies
29
Views
9K

Hot Threads

Recent Insights

Back
Top