NEA-1627 BOT3P2.0.

1. NAME OR DESIGNATION OF PROGRAM:  BOT3P2.0 (Bologna Transport Analysis Pre-Post-Processors Version 2.0)

3. DESCRIPTION OF PROGRAM OR FUNCTION

BOT3P Version 1.0 was originally conceived as a set of standard FORTRAN 77 language programs in order to give the users of the DORT and TORT deterministic transport codes, included in the DOORS-3.2 software package,  some useful diagnostic tools to prepare and to check their input data files. BOT3P Version 1.0 permitted to overcome some big difficulties in the preparation of the geometrical model entries and of the fixed neutron source entries of the ENEA-Bologna DORT/TORT input files for the shielding calculations of the VENUS-1 and VENUS-3 benchmark experiments, within the framework of the activities of the OECD/NEA Task Force on Computing Radiation Dose and Modelling of Radiation-Induced Degradation of Reactor Components (TFRDD).

BOT3P Version 2.0 extends the possibility to produce also the geometrical, material distribution and fixed neutron source data for the deterministic transport codes TWODANT and THREEDANT of the DANTSYS system. In other words, it is now possible to get at the same time two files absolutely equivalent as for the data contents, one for DORT/TORT and the other one for TWODANT/THREEDANT starting from the same BOT3P input. However the plotting capabilities are so far limited to the DORT/TORT data files produced by BOT3P.

The following programs are included in the BOT3P software package: GGDM, DDM, GGTM, DTM2, DTM3, and RVARSCL.

- GGDM requires in input all the geometrical, material and fixed neutron source information to generate the fine mesh boundary arrays, the material density factor for each fine space mesh array, the material number for each material zone array and the distributed source distribution array for DORT/TWODANT (two dimensional (2D) transport applications) for both  X-Y and R-THETA geometries.

- GGTM is the "twin" code of GGDM for three-dimensional (3D) applications. It requires in input all the geometrical, material and fixed neutron source information to generate the geometrical, material and distributed source distribution arrays for TORT/THREEDANT for both X-Y-Z and R-THETA-Z geometries.
The main feature of GGDM and GGTM consists in de-coupling the geometrical model description, which must be prepared once and for all, and the mesh grid refinement options.  If users decide to create a more or less refined mesh compared  the one they already have or to switch from a X-Y/X-Y-Z mesh grid to a R-THETA/R-THETA-Z mesh grid or vice versa, it is sufficient for them to change very few data entries and to run GGDM/GGTM again, without modifying the geometrical description of the model to be analysed. Both GGDM and GGTM can also produce the data entries related to the presence of a fixed volumetric isotropic neutron source as a function of the generated mesh.
Users can define model areas/volumes with a more (or less) refined mesh grid with respect to the standard one for all the geometry.  Moreover, GGDM and GGTM allow to define "very small" geometrical zones centred about the key flux positions for edit purposes. That gives users the possibility to get the target quantity values in such locations directly from the transport code outputs as region response averages, without any need to interpolate the cell results.

- DDM is a DORT graphics pre/post processor and it allows users to check the correctness of the entries generated by GGDM by plotting the geometry, the material mixture distribution or the fixed neutron source distribution, if any. DDM can work as a DORT post-processor also, by displaying any non-negative scalar target quantities of the transport analysis, such as, for example, the scalar neutron flux.

- DTM2 and DTM3 allow users to check the correctness of the entries generated by GGTM by plotting the geometry, the material mixture distribution or the fixed neutron source distribution, if any, in two dimensional plots and three dimensional plots, respectively. Both DTM2 and DTM3 can work as TORT post-processors also, by displaying any non-negative scalar target quantity of the transport analysis, such as, for example, the scalar neutron flux.
DTM2 makes 2D cuts of the model normal to one of the 3 co-ordinate directions X-Y-Z / R-THETA-Z and plots the material distribution or any non-negative target quantity on those cuts.
DTM3 can make 3D parallel projections of a selected set of model material mixtures in a user defined model volume by reproducing the material distribution or a target quantity distribution on the visible surfaces of the selected model.
DDM, DTM2 and DTM3 generate plots by using the RSCORS Graphics System subroutines which are included in (at least up to) the DOORS-3.3 software package together with DORT and TORT.

- RVARSCL can read a VARSCL sequential format file produced by DORT and TORT when the discontinuous space mesh option is not used, and can write a new binary sequential format file according to the input requirements of the post-processors DDM, DTM2, DTM3.  RVARSCL gets the spatial distribution of the scalar neutron flux as the result of the sum of a selected number of energy groups. It accepts any user's non-negative weight (response) input function too, depending only on the energy group structure used in the DORT/TORT analysis, to be multiplied by the scalar neutron flux obtained in the DORT/TORT transport calculations.

Moreover, BOT3P Version 2.0 contains some important additions with respect to Version 1.0, which enlarge its potential applicability range, and precisely:

-- New geometrical objects, conventionally called geometrical windows in BOT3P manuals, can be input now for X-Y/X-Y-Z mesh grids, such as rods and hexagons very suitable to describe a nuclear reactor core lattice in a detailed way. The circular/hexagonal sections of these geometrical objects can be simulated by  "stair-cased" border, as refined as desired by the user, strictly respecting their exact area value.

-- For clarity's sake, the so called "absorber zones" of BOT3P Version 1.0 have no longer input modalities different from the other geometrical windows. They can be input as square section windows strictly respecting their exact section area value, both for X-Y/X-Y-Z mesh grids and R-THETA/R-THETA-Z ones, in the BOT3P input section  normally reserved to geometrical windows.

-- The so called "truncated right angle cone window", with axis of arbitrary orientation in space, can now be input both for X-Y-Z mesh grids and R-THETA-Z ones. A proper sequence of these windows lets users generate as complex as desired revolution solids with axis of arbitrary orientation in space.

-- The so called "detectors/detector zones" of BOT3P Version 1.0 can be practically defined as "edit zones" centred about key flux positions where to get results without the need for interpolation of mesh results. They are dealt with by Version 2.0 in a much simpler way and the related input modalities have been uniformly standardised for both 2D and 3D applications.

-- Material zones have density factors as additional input parameters in BOT3P Version 2.0. They are very useful, because they allow users to respect the total mass and reaction rates when the material zone areas/volumes are affected by approximations due to the mesh grid simulation. That means that BOT3P automatically generates the 3**/7** DORT/TORT arrays and the corresponding optional entry "den" of the input data block 5 for TWODANT/THREEDANT.

-- Users can specify an arbitrary range for the neutron source or for a target quantity to be plotted in 2D  plots (DORT models and TORT model cuts)  instead of the default (target quantity minimum/maximum values).

4. METHODS

GGDM and GGTM work similarly from the logical point of view. Since the 3D case is more general, the following description refers to GGTM.
All the co-ordinate values which characterise the geometrical scheme at the basis of the TORT/THREEDANT geometrical and material model are read, sorted and all stored if different from the neighbouring ones more then an input tolerance established by the user. These co-ordinates are always present in the fine-mesh boundary arrays independently of the mesh grid refinement options, because they describe the user's scheme. According to the mesh grid refinement options, GGTM introduces further co-ordinate values, which complete the TORT input mesh grid. A loop for each cell is performed to determine the zone and the material to be attributed to the cell. The cell is ideally represented by its centre and it is relatively simple to determine which material zone the cell belongs to. Material zones may have very complicated geometrical shapes in space thanks to the combinatorial geometry among volumes existing in GGTM. Bodies are generated (only for TORT) by aggregating neighbouring cells belonging to the same zones, taking care to fill up all the geometrical domain of the model. Fixed neutron sources, if any, are adapted to the mesh refinement at the same time.

As for the plot programs DDM, DTM2 and DTM3, they do not make any value interpolations among cell values to have contours, when used as post-processors or to plot any fixed neutron source distribution; they simply attribute the entire single mesh grid cell the colour corresponding to the adopted value scale. This simple and fast method lets users faithfully reproduce TORT results and overlap material, zone, body or mesh borders on the same plots without overcrowding them with too many lines.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

Only a continuous space mesh grid can be generated by GGDM and GGTM and input to DDM, DTM2, DTM3 and RVARSCL.

6. TYPICAL RUNNING TIME

Central processor unit (CPU) time is roughly proportional to the number of cells the 2D/3D models created by GGDM/GGTM consist of. The CPU time for GGDM/DDM applications can be considered negligible with modern hardware performances. For 3D applications, the distributed source distribution array generation may really be time consuming for the R-THETA-Z model if a core simulating neutron source is present.

Just to give an idea of the typical running time of GGTM, it is worth while mentioning that the CPU times required by BOT3P Version 1.0 to produce the ENEA VENUS-3 X-Y-Z and R-THETA-Z models, distributed source distribution array included, were respectively 148 s and 293 s on a DIGITAL UNIX ALPHA 500/333 workstation. Both models were more or less one million cells large. BOT3P Version 2.0 is a little slower than Version 1.0, since it has to prepare the TWODANT/THREEDANT model in addition to the DORT/TORT one.

8. RELATED OR AUXILIARY PROGRAMS

DOORS-3.2:  One-,Two-, and Three-Dimensional, Multigroup, Discrete-Ordinate Transport Code System
DANTSYS 3:  One-,Two-, and Three-Dimensional, Multigroup, Discrete-Ordinate Transport Code System"

10. REFERENCES

? W.A. Rhoades, R.L. Childs., RSIC Computer Code Collection DOORS-3.1, DORT: A Two-dimensional Discrete Ordinates Transport Code, RSIC Code Package CCC-650, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
? W.A. Rhoades, D.B. Simpson, The TORT Three-dimensional Discrete Ordinates Neutron/Photon Transport Code (TORT Version 3), ORNL/TM-13221, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
? RSIC COMPUTER CODE COLLECTION DOORS-3.2, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA, distributed by RSICC and OECD/NEA-DATA BANK.
? S.L. Thompson, The RSCORS Graphics System, Sandia National Laboratories, Albuquerque, New Mexico, U.S.A., "The RSCORS (Version 3.13) Reference Manual".
? R.E. Alcouffe, R.A. Baker, F.W. Brinkley, D.R. Marr, R.D. O'Dell, W.F. Walters, "DANTSYS 3.0: One-,Two-, and Three-Dimensional, Multigroup, Discrete-Ordinate Transport Code System", LA-12969-M, Los Alamos National Laboratory, Los Alamos, New Mexico, USA (1995).
? M. Pescarini, M.G. Borgia, R. Orsi,  T. Martinelli, ENEA-Bologna Validation of the BUGLE-96 ENDF/B-VI Library on the VENUS-1 Neutron Shielding Benchmark Experiment. A Synthesis of the Final Results, JEF/DOC-778, JEFF Working Group Meeting on Benchmark Testing, Data Processing and Evaluations, NEA Data Bank, Issy-Les-Moulineaux, April 12-14, 1999.
? Prediction of Neutron Embrittlement in the Reactor Pressure Vessel: VENUS-1 and VENUS-3 Benchmarks, NEA/NSC/DOC(2000)5, OECD/NEA-DATA BANK.
? M. Pescarini, R. Orsi, M.G. Borgia, T. Martinelli, ENEA Nuclear Data Centre Neutron Transport Analysis of the VENUS-3 Shielding Benchmark Experiment, KT-SCG-00013, ENEA-Bologna, Italy.
? R. Orsi, The ENEA-Bologna Pre-Post-Processor  Package BOT3P for the DORT and TORT Transport Codes, JEF-DOC/828, JEFF Working Group Meeting on Benchmark Testing, Data Processing and Evaluations, NEA Data Bank, Issy Les Moulineaux, France (May 22nd-24th 2000).
? R. Orsi, RVARSCL - A Post-Processor to Deal with the "VARSCL" Sequential Format Files in Output from the DORT and TORT Discrete Ordinates Transport Codes, KT-SCG-00010, ENEA-Bologna, Italy.
? R. Orsi, GGDM, DDM - The ENEA Nuclear Data Centre Pre/Post-Processors of the DORT Discrete Ordinates Transport Code, KT-SCG-00011, ENEA-Bologna, Italy.
? R. Orsi, GGTM, DTM2, DTM3 - The ENEA Nuclear Data Centre Pre/Post-Processors of the TORT Discrete Ordinates Transport Code, KT-SCG-00012, ENEA-Bologna, Italy.

11. HARDWARE REQUIREMENTS

The author has run BOT3P Version 2.0 programs on a DEC Alpha system and on P.C. under  Red Hat Linux.  But they are very likely to run on most UNIX W.S.

13. SOFTWARE REQUIREMENTS

Up to now BOT3P has been successfully tested under the following UNIX and LINUX systems:
DEC Alpha, OSF1 V4.0F, DIGITAL Fortran, Version 5.2;
personal computer, Red Hat Linux 7.0 and 7.1, g77 version 2.96 20000731 (from FSF-g77 version 0.5.26 20000731);
Sun Ultra 10, Solaris8, Fortran 77 version 4.2.

BOT3P Version 1.0 was successfully tested on the following UNIX system: IBM RS/6000, AIX 4.3.2, XLF 3.2.5.
Now it is no longer  available to the author, that's why it was impossible for him to test BOT3P Version 2.0 on such platform. However, there is no reason that BOT3P Version 2.0 would not run on IBM W.S. too.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

DDM, DTM2 and DTM3 call many RSCORS Graphics System subroutines. The compiled library where the graphical primitives are grouped, named librscors.a (see DOORS documentation), must previously have been compiled with NO OPTIMIZATION when installing DOORS.

It must be remembered that DDM, DTM2 and DTM3, if used in combination with DORT/TORT geometrical and compositional models not coming out from GGDM/GGTM, can read only the FIDO free format with some limitations reported in the user manuals.

DTM3 can generate up to ten different frames per run. However for very large geometrical models, users are suggested to generate not more than 2 or 3 frames in the same DTM3 run in order to avoid too big metafiles and postscript files.

15. NAME AND ESTABLISHMENT OF AUTHORS

Roberto Orsi
ENEA   C.R.E.  E. Clementel  
ENEA FIS-NUC
Via Martiri di Monte Sole, 4
I-40129 Bologna
Italy