Code Manual for CONTAIN 2.0 - Federation of American Scientists

discussed in Section 4.2 prior to specifying the flow path elevation and in
particular should note that a flow path connected to the top of a cell is treated ~
differently from side-connected or bottom-connected paths. In general, the
robustness of the code will be improved if the gas head space associated with
the onset of gas or pool flow in a side-connected path is fairly substantial (on
the order of 20% of the cell volume). Side-connected paths attached very
close to the top of the cell are not recommended. To avoid accidental
specification of such a side connection when a top connection is intended, it
is recommended that the user rely on the CELLHIST input in the cell
GEOMETRY block to speci@ cell elevations directly, rather than rely on
values that would otherwise be calculated by the code from the initial cell gas
center-of-volume elevation, the cell gas “height,” and the initial gas and pool
volumes. (m)
FPCOSN,i,j the cosine of the angle of the flow path axis with respect to the vertical
= fpcosn direction. The angle is measured between the upward direction and the flow
path axis in the direction from i to j. The value is used to calculate aerosol
settling through the flow path. The value for “fpcosn” should be 1 if the end
of the flow path at cell j is directly above that at cell i, and -1 if the reverse
is true. Only the component of aerosol settling velocities parallel to the flow
path axis is considered. Default= O. (dimensionless)
B. 1.4 Alternative Global AEROSOL Keyword Format
The global AEROSOL keyword may be followed by an optional parameter string.
AEROSOL [newcof diaml diarn2 tgasl tgas2 pgasl pgas2]
The parameters have the following definitions:
newcof flag for calculating aerosol coefficient sets. Default=l.
diarnl aerosol minimum diameter. Default = 1.0x 10-7..(m)
diarn2 aerosol maximum diameter. Default = 1.0x 104. (m)
tgas 1 lower interpolation temperature. Default = 273. (K)
tgas2 upper interpolation temperature. Default = 673. (K)
pgasl lower interpolation pressure. Default = 5.0x 104. (Pa)
pgas2 upper interpolation pressure. Default = 8.0 x 105. (Pa)
The above parameters are followed by the rest of the global aerosol input block, discussed in Section
14.2.5. If a keyword entry following the above parameters redefines any of the parameters in the
Rev O B6 6/30/97