As mentioned above, the fluid on the high-pressure tube-side can be a mixture of vapoureliquid. Following partial or full-bore
tube rupture this mixture can flow through the break into the
low-pressure shell-side in either of the following two forms:
i) Isentropic expansion of the mixture from the chamber at the
tube-sheet process side (either at the hot side or the cold side of
the exchanger) into the LP shell-side.
ii) Adiabatic frictional expansion of the mixture from the respective
chamber along the tube (of length L) to the tube rupture
location