Water Hammer & Slug Force

[raam]

Dear Friends,

I am analyzing a 20” condensate blow down line using CAESAR II software.

From two vessels, two 6” condensate line outlets connects with two separate control valve (ESDV) arrangement and this line further expands as 12”. This both 12” line after 10m connects with a 20” blow down header.

During shutdown both esdv is supposed to open fully to depressurize the two vessels (approximately in 15 min duration). Control valve allows 4 bar at the downstream.

My question is,

1. Is there a chance of water hammering effect in the downstream (12” & 20” line) of valve.

2. Or because of the sudden pressure reduction near to the valve is there any chances of slug flow.

3. Is it Possible for Both Water hammer & Slug force ?

Without considering both (water hammer & slug force) system passes. Kindly throw some light on this issue. Thanks in advance.

[FATHI]

I believe , for water hammmer is to start with the rough formula of Joukovsky , It gives a good approach for estimating the surge pressure , which you have to add onto your design pressure , to select the correct flange rating. You have a lot of sites for that , but I can estimate it yourself if you know the speed, density , thickness , modulus of young

With Caesar it is a dynamic issue and you will tret the mode shape and and see ultimately where to put your axial supports ; on which you will have hignloads
suggest you go to coade site = coade.com
Also Caesar has a worked example , I Suggest to study it