Code Manual for CONTAIN 2.0 - Federation of American Scientists

with a discussion of the implementation approach taken to ensure that the core physics modules are
identical among the stand-alone, CONTAIN, and MELCOR implementations of CORCON Mod3.
5.7.1 Implementation Strategy
Major architecture changes were made to the CORCON Mod3 software to facilitate its
implementation into CONTAIN. Most notably, an architecture was developed to allow CONTAIN
and MELCOR implementations of CORCON Mod3 to share a common set of routines that embody
the key physics models. Unique interface routines were then developed to link the common
CORCON models to the CONTAIN code. A parallel effort was also undertaken to develop the
necessary interface to link MELCOR to the common CORCON models. This strategy for linking
CORCON to CONTAIN and MELCOR is illustrated in Figure 5-4. This approach has two key
advantages:
c It ensures that the same physics modeling is used in the CONTAIN, MELCOR, and
stand-alone implementations.
● Improvements made to the core physics models will be reflected in all three
implementations with little or no code development effort.
As a result of this strategy, many of the subroutine names in CORCON Mod3 have been changed
from the names referred to in Reference Bra93. All CORCON-related routines in the core physics
module now begin with the two letters CC, and all VANESA-related routines in the core physics
module now begin with the two letters VA.
5.7.2 Obsolete Options From CORCON Mod2
A number of options were included in the CONTAIN implementation of CORCON Mod2 that have
not been retained in the CORCON Mod3 implementation. Instead of specific options, CORCON
Mod3 provides new user flexibility options that provide much of the required flexibility for
sensitivity studies. These new user flexibility options have been fully implemented. Therefore, the
decision was made to remove the previously provided user options that were not part of the new
capability. The keywords that are no longer available include: CONCCOMP, EDITDELT, REBAR,
FDELT, DIFCO, BUBD, PTBB, PTDIA, OXPDT, MOLEC, STABLE, MMCHEM, ISCHEM,
VROVR. All of the input for these options is still accepted, but will produce an input warning
message. If an existing input file containing one of these keywords is used, the user should check
to see whether one of the new user flexibility options will provide a similar function.
5.7.3 Nonstandard Gases Released From CORCON
During CCIS, CORCON may release some gas species that are not included in the CONTAIN
material library. Normally, such gases are treated by CONTAIN as nitrogen in molar-equivalent
quantities. The NOUNKGAS optional keyword in the CORCON input block is provided to restrict
the chemistry in CORCON to producing only gases in the CONTAIN material library: CO, COZ,
Hz, and HZO.
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