Ennis et al. (2011a and 2011b) recognized four distinct phases of a tube rupture scenario where a high-pressure sub-cooled flashing
liquid is released into a liquid-filled low-pressure heat exchanger
shell. These four phases are associated with systems where relief
valves and/or rupture discs are employed. In cases where none of
these are employed, only the first phase is applied, which is related
to the pressure buildup (surge) due to the accumulation of the
effluent fluid in the exchanger shell. This is the most important
phase and is the subject of this paper. Upon a full-bore tube rupture,
the process fluid in the tube (which could be a mixture of vapour
and liquid) will expand from the high-pressure tube-side and will
cause the pressure on the shell-side to increase. The rate of pressure
increase as well as the maximum pressure reached depends on the
following parameters: