Total condenser - tube rupture case

[laliyo]

Hello,

I have a total condenser (inlet 100 % vapor - Outlet 100% Liquid), where based on design pressure ratio of Shellside/Tubeside, the catastrophic tube rupture is a valid case.

Now , if the fluid is 100% vapor on both side or 100 % liquid on both side or 2-phase on both side, I know how to calculate the required relief rate, based on appropriate method (such as 2-orifice or Orifice-tube).

But for a condenser, where one side is vapor and one side is liquid , how to determine relief load? Can I individually calculate flows on both sides ( using vapor on one side and flashing liquid on other side) and determine the resultant stream ?

thanks in advance.

 

[CJKruger]

laliyo, rightly or wrongly, in the past I have only done the tube rupture case assuming the break occurs at the vapour end.

 

[koshyeng]

My amateur thoughts:

When tube ruptures, system will have high pressure side fluid in whole exchanger and you would be relieving high pressure side fluid.

You have to find if the liquid is flashing, critical vapor or non critical and size relieving rate accordingly.

Seek Jedi's thoughts too.

 

[ajs1972]

It is necessary to install a pressure relief valve on the low pressure side when the design pressure of the
low pressure side is less than three-quarters (75%) of the design pressure of the high pressure side.

If the high pressure side of the exchanger operates at 1000 psig or more and contains a vapor or a liquid
that can flash or it vaporizes liquid on the low pressure side, complete tube failure should be considered
regardless of the pressure differential.