MULTIVOL an extension of the BIVOL blowdown code to a higher number of volumes

The name of the code BIVOL indicates that essentially two (bis) control volumes are considered to determine the thermohydraulic behaviour of the loop. The code BIVOL gives appreciable results in simple cases and is very helpful in parameter studies. Being limited to two volumes, however, the code cannot describe the effect of cold water injection lines or other additional volumes in the loop. It was desirable to extend the capabilities of BIVOL to a higher number of control volumes, i.e. to go over from BIVOL to MULTIVOL. This reports presents the description of the MULTIVOL code (task of MAIN, modelling in MAIN, subroutine ALFA, subroutine QWALL), its application (nodalization, entrance data preparation), and the listing