Code Manual for CONTAIN 2.0 - Federation of American Scientists

nat the number of cell atmospheres to be solved implicitly.
(icell) a list of “nat” cell numbers, corresponding to the cells with atmospheres to be
solved implicitly.
POOLS a keyword to specify the pools to be solved implicitly. If POOLS or “nimpli”
is not specified, but IMPLICIT is, all pools will be solved implicitly.
npl the number of pools to be solved implicitly. This maybe zero.
(jcell) a list of “npl” cell numbers, corresponding to the cells with pools to be solved
implicitly, if “npl” is non-zero.
DROPOUT the keyword for removing all suspended liquid coolant from the atmosphere
and depositing it in the appropriate pool, as determined by the OVERFLOW
option discussed in Section 14.3.1.12.
PERROR the keyword for defining the degree to which the inventory of a cell, as
measured by the pressure, is iterated to self-consistency. The error in the
pressure difference between cells gives rise to an error in the flow rate. The
cumulative error in the flow over the timestep leads to an inventory error.
This is what is limited by “perror.” (For very large flow areas, the driving
pressure differences between cells have errors much less than “perror.”)
perror the value of the self-consistency error. Default= 1. (Pa)
PIVOTMIN the keyword for defining the minimum acceptable size of a divisor in the
implicit solver analogous to the pivot element in Gaussian elimination. A
smaller divisor is assumed to generate an effectively singular inverse matrix
and is not used.
pvtmin the minimum size of the pivot element. Increasing the value somewhat
should increase robustness, at the expense of efficiency. The decrease in
efilciency should be acceptable for a factor of two to four increase in value.
Default = 0.01. (dimensionless).
FIX-FLOW the keyword for activating the FIX-FLOW option for implicit cell
atmospheres.
(rtol) the rate tolerances for the FIX-FLOW option, corresponding to qiin Equation
(4-28) in Section 4.4.9. This tolerance will be applied to atmosphere
temperature, mass, and gas volume relative rates of change to determine
whether the cell atmosphere may be replaced by a fixed flow boundary
condition in the implicit solver. Speci~ a string of tolerances, one for each
cell in the problem, in order of cell number. A zero value for a tolerance
Rev O 14 24 6/30/97