-3-
y
a
One
of the major coces that was moci-ied !s sarHew lh), its gurpose 135 to
adjust voserved winds, using variational anaivsis methocs, so as to conserve M33
rrom eell to cell.
After modification, all observed uoper air wind data from 19m to
33 xm were entered as input. This ‘vas done for four time periods, using winds for
one to three onserving stations for each time. The oovious advantages of this code
(over most other fallout codes) is that mass is not permitted to accumulate in any of
the cells and winas are available for each 3-D cell intersection for four times.
Tne MATHEWwinds are used then by the modified appicl’! particle-in-eell
code
to calculate
source.
allowing
the transport,
diffusion,
and
deposition
of an
instantaneous
Modifications required of ADPIC, to handle the Bravo test, consisted of
more
upper
air
input
than
is
used
in
tvpical
ARAC
assessments.
Furthermore, since particles falling from the stratosohere undergo a larga increase *
in air density, it was necessary to add a turoulent wake correction to the larger
;
.
.
(4
oarticles; this correction follows the method set forth by AleDonald.
Other
modifieations were to incorporate a tropical atmosphere into the fall velocity
calcuations and to make the particle activity increase as the cube of particle
cacius.
Finally, time-integrated deposition was acded; this allows calculation of the
total dose from detonation time to evacuation.