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[Sue N]

I have a question regarding API 521 (6th Edition) section below about the location of a relief device relative to a heat exchanger. (See below for section). 

 

4.4.14.2.3 Relief Devices and Locations The design of piping around the exchanger and the location of the relieving device are both critical factors in protecting the exchanger. Both rupture disks and PRVs should be considered. It may be necessary to locate the relieving device either directly on the exchanger or immediately adjacent on the connected piping. This is especially important if the low-pressure side of the exchanger is liquid-full. In this case, the time interval in which the shock wave is transmitted to the relieving device from the point of the tube failure increases if the device is located remotely. In addition, there is a time delay for the gas to overcome the momentum of the liquid filled low-pressure side prior to establishing a full flow through the relief path. This can result in higher transient overpressure on the exchangers before operation of the rupture disk or relief valve.

 

I am having some trouble finding methods to calculate the transient pressure on the shell side of the exchanger should a tube rupture occur.  Can anyone recommend a reference book or article where I can find a method?  Thank you for your help.