Understanding Water Hammer in Jacketed Pipes: Causes and Analysis

  • Thread starter maxx_payne
  • Start date
  • Tags
    Water
In summary: In the original post, the author said the pipe failed due to water hammer. The water hammer effect is when the pressure in a fluid stream (such as water) exceeds the pressure at the walls of the pipe. The pressure wave travels along the length of the pipe and can cause damage. To analyze water hammer in a system, you need to know the dimensions of the system (area and cross-sectional dimensions), the properties of the fluid (vapor, liquid, or gas), and the properties of the components (e.g. valve, pipe, and jacket). You can also use an online water hammer calculator.
  • #1
maxx_payne
86
0
IN MY WORK a jacketed pipe was damaged i duno whts the reason but i doubt the water hammer
can anyone help me about the analysis of water hammer in jackets
 
Engineering news on Phys.org
  • #2
Do you have a fast acting valve upstream of where the pipe failed?
 
  • #3
yes the pipe is 6 meters with 3 mm thickness and 1st tube is 6" dia and the outter tube is 8" dia,eter ,, and the fluid between pipes is coolin water under 4 bars how can it be a water hmmer ??
 
  • #4
holla guys help meeeeeeeeeee in this problem
 
  • #5
Ask a question that means something and perhaps you will get some more help. From your previous answer I can not tell if you have a fast acting valve upstream. Do you? That is the cause of water hammer in most cases.
 
  • #6
yes we have this fast actin valve but how can i make the water hammer analysis in the annular ? can u tell me the required equation ?? and how can i make an equivelent pipe for the annular to ease the calculation ??
 
  • #7
All right. I have a pretty good paper somewhere that covers water hammer in spacecraft systems. It should be applicable. Let me see what I can dig up.

EDIT: I can't post the paper here because it is copyrighted. However the particulars are:
Waterhammer in a Spacecraft Propellant Feed System Journal of Propulsion and Power, Vol 8 No.3, May-June 1992.
I would recommend getting a copy of it for yourself. It is not that expensive.
 
Last edited:
  • #8
I Dont know but if u can tell me about the maximum pressure wave value for the hammer pressure in my annular ??
 
  • #9
maxx_payne,

Here is an on-line calculator for water hammer;

http://www.lmnoeng.com/WaterHammer/WaterHammer.htm

In your case, the value of A (Pipe cross-sectional area) will be the annulus area and the value of f (Darcy-Weisbach friction factor) should be adjusted to recognize that two (2) surfaces are presented to the flowing fluid... the interior of the jacket and the exterior of the process pipe. Other adjustments may need to be made due to your special situation.

If you doubt that water hammer is the cause of the damage, what other mode do you suspect?

I can imagine a case where the inside process pipe could be damaged through design or operational error if;
1. The process fluid is in the vapor phase
2. The jacket fluid is cooling water
3. The process pipe is isolated for a length of time sufficient for the process fluid to condense
4. The process pipe is underdesigned such that it cannot withstand the resulting differential pressure and therefore collapses.

On the other hand, if water hammer is the culprit and the valve is motor operated, then the rate of closure can be decreased or if it is a control valve, the manufacturer might have an alternative trim which would solve the problem, see;

http://www.engineeringtoolbox.com/control-valves-flow-characteristics-d_485.html
.
 
  • #10
maxx_payne said:
IN MY WORK a jacketed pipe was damaged i duno whts the reason but i doubt the water hammer
can anyone help me about the analysis of water hammer in jackets

If you doubt it was due to the water hammer effect, why do you want to analysis water hammer effects?

How exactly did the pipe fail? This will provide more insight as to what the failure mode was.

CS
 
  • #11
1st the inner pipe was collabsed as if u can imagine its cross section became as an 8 approximately ,, and the failure was only in the jacketed parts
frankly i have to reason to think about
1- water hammer
2- thermal stresses ??
so i need the analysis of the water hammer to find out the solution for this problem
 
  • #12
1st the inner pipe was collabsed as if u can imagine its cross section became as an 8 approximately ,, and the failure was only in the jacketed parts
frankly i have to reason to think about
1- water hammer
2- thermal stresses ??
so i need the analysis of the water hammer to find out the solution for this problem
 
  • #13
I'm the least qualified to answer here, but there are a couple of things that I should mention. One is that most (not all) of us have English as a first language, so your postings are a bit hard to follow. Secondly, although you mentioned the dimensional specifications of your pipes, you didn't say what they're made of. There'll be one honking big difference between aluminum and 1812 stainless steel.
Past that, I leave it to the experts.
 
  • #14
well am sorry for my bad english , the pipe is made of stainless steel 304
with thickness 3 mm and length of 6 meters
 
  • #15
In fact, having seen your posting in a (currently) following thread (How to...?)
You don't seen to have trouble with English when you apply yourself. :smile:
 
  • #16
where is the comment about the main problem of the analysis of the water hammer inside the annular ?
 

1. What is water hammer in annular?

Water hammer in annular is a phenomenon that occurs in pipes where a sudden change in the flow of water causes a pressure surge or shock wave. This can lead to loud banging noises, vibrations, and potential damage to the pipe and surrounding structures.

2. What causes water hammer in annular?

Water hammer in annular is caused by the sudden change in velocity of the water flow, which can be due to various factors such as a valve closing too quickly, a pump shutting off abruptly, or a sudden change in the direction of the flow.

3. How does water hammer in annular affect the pipe?

The pressure surge caused by water hammer in annular can exert a great amount of force on the pipe, leading to potential damage such as cracks, leaks, or even burst pipes. The repeated occurrence of water hammer can also weaken the pipe over time.

4. How can water hammer in annular be prevented?

There are several ways to prevent water hammer in annular, such as installing pressure relief valves, using air chambers or surge tanks, and ensuring gradual changes in the flow of water. Regular maintenance and inspection of pipes can also help identify and prevent potential causes of water hammer.

5. Can water hammer in annular be fixed?

Yes, water hammer in annular can be fixed by identifying and addressing the underlying cause. This may involve adjusting the water flow, installing additional components, or repairing any damage to the pipe. It is important to address water hammer promptly to prevent further damage and maintain the integrity of the pipe system.

Similar threads

Replies
3
Views
3K
  • Mechanical Engineering
Replies
12
Views
2K
  • Mechanical Engineering
Replies
15
Views
816
  • Mechanical Engineering
Replies
28
Views
2K
  • Mechanical Engineering
Replies
31
Views
2K
Replies
8
Views
2K
Replies
4
Views
1K
  • Mechanical Engineering
Replies
8
Views
3K
Replies
13
Views
2K
  • Mechanical Engineering
Replies
9
Views
812
Back
Top