 |
The analysis of
cylindrical sources, which through user-specified input can be modeled to represent
miniature sources, line sources, disc sources, ring and thin-crescent sources (through the
combination of disk sources and penetrations with plugs), cylindrical shells (through the
combination of large cylindrical sources), semi-infinite media (at any density), and
infinite media
|
|
Built-in specifications
for 216 pipes (ranging from 1/4"Sch10S to 36"Sch40), for automatic source radius
and wall thickness definitions
|
|
Optimized, built-in
source-meshing algorithms for carefree applications
|
|
Multiple cylindrical
containers with user-specified side-wall and end-wall thicknesses symmetrically positioned
around the source (user input may reduce each container to a lateral sleeve, or to disks
on both ends of the source)
|
|
Multiple shield slabs
positioned either parallel or at right angles to the source axis
|
|
Receptors positioned
anywhere inside the source, or at any source surface
|
|
Receptors positioned on
end [external to the source and at distances from the source axis less than the source
radius], at locations external to all shield slabs and/or containers
|
|
Receptors positioned on
side [external to the source and at radial distances from the axis greater than the source
radius and at any elevation with respect to the source], at locations external to all
shield slabs and/or containers
|
|
Plugged penetrations for
receptors on end, with the penetration material in each container and shield slab being
user specified (receptor locations are limited to positions along the penetration axis)
|
|
Choice of 26 materials
for the source, containers, shield slabs and receptor medium, with default (built-in) or
user-specified densities
|
|
Material-sequence-dependent
buildup factor formulation
|
|
User-specified
time-dependent gamma spectra (with energies in the range 0.010 to 15 MeV), or internally
calculated 18-group spectra based on user-specified radionuclide inventories [101-nuclide
data base, with internally defined inventories for daughter products in secular
equilibrium with their parents (for cases where the parent inventory is user specified and
that of the daughter product is not), though without decay correction]
|
|
Computation of
time-dependent dose rates to air (in rad/hr), and time-integrated interval and cumulative
doses (rad), for the following:
 |
A single source and
multiple receptors, or |
|
Multiple sources and one
(and the same) receptor, the contribution from any given source being either additive or
subtractive, at user specification
|
|
|
A typical geometric
arrangement acceptable by the software is shown in Fig. E.1.
The user need only provide the following:
|
General information
regarding the handling of the source (single or multiple source geometries), any source
intensity adjustment, and orientation of the shield slabs |
|
The source dimensions,
material and density for each container and each slab, the container dimensions, materials
and densities, along with the material and density of the plug for any penetration that
may traverse the container |
|
The receptor medium
(material and density) |
|
The receptor location(s)
of interest, and the diameter of any associated penetration that may affect any of the
each receptors, and |
|
Either the
time-dependent gamma spectra or a radionuclide inventory
|
|
|
Typical applications of
the software include the following:
|
Radiation levels from
radioactive recirculating fluids under Loss-of-Coolant-Accident (LOCA) conditions (for the
determination of vital-area accessibilities and required shielding, and component
radiation damage) |
|
Radiation monitor
response determinations (as required for the correlation of monitor readings with
emergency action levels) |
|
Design of
monitor/chamber geometries for sampling gaseous radioactive effluents under normal and
accident conditions |
|
Spent-fuel pool
radiation levels (for the determination of water depth requirements, and potential
radiation damage to immersed components) |
|
Evaluation of
shipping-cask external radiation levels (spent fuel or other) |
|
Shielding calculations
related to on-site storage of low-level and high-level waste |
|
Evaluation of radiation
levels from waste disposal tanks, etc.
|
|
|
FORTRAN 77; 4600 coded
lines; DOS and UNIX applications; ASCII file input; 132-column output
|
|
The validity of DIDOS-5E
has been verified through extensive testing and through comparative analysis with
information available in the literature. In general, dose rates were found to be within a
few percent of expected values, including receptors embedded in infinite media of any
density, where the energy-conservation principle applies (energy absorbed = energy
produced). |
