RSICC CODE PACKAGE PSR-525

1. NAME AND TITLE

BOT3P3.0: Code System for 2D and 3D Mesh Generation and Graphical Display of Geometry and Results for Radation Transport Codes.

AUXILIARY ROUTINES

RVARSCL: Reads DORT/TORT "VARSCL" sequential format files.

GGDM: Generates the geometric and material entries for DORT.

DDM: Plot program used as a DORT pre/post processor.

GGTM: Generates the geometric and material entries for TORT.

DTM2: 2D Plot program used as a TORT pre/post processor.

DTM3: 3D Plot program used as a TORT pre/post processor.

2. CONTRIBUTORS

ENEA Nuclear Data Center, Bologna, Italy, through the OECD Nuclear Energy Agency Data Bank, Issy-Les Molineaux, France.

3. CODING LANGUAGE AND COMPUTER

Fortran 77; DEC Alpha, Sun, IBM RS/6000 and PC Linux (P00525MNYCP00).

4. NATURE OF PROBLEM SOLVED

Bologna Transport Analysis Pre-Post-Processors (BOT3P) is a set of standard Fortran 77 language programs developed at the ENEA -Bologna Nuclear Data Center. BOT3P Version 1 was conceived 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 users to overcome difficulties in preparing the geometrical model entries and 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 the geometrical, material distribution and fixed neutron source data for the deterministic transport codes TWODANT and THREEDANT of the CCC-547/DANTSYS system making it possible to get 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.

BOT3P3.0 contains some important additions with respect to BOT3P2.0, and precisely:

• •Users can specify areas/volumes of the model where the zone/material distribution may be defined by both a combinatorial geometry and an external source, such as, for example, one or more existing DORT/TORT input file/s and files derived from CT scans (for 3D applications only). If the external TORT input file/s were previously generated by BOT3P, the perfect reproduction of both material zone shape and volume values of the partial domains transferred into the new 3D model is assured, because all the co-ordinates defining bodies are also included in the fine mesh arrays. For a file derived from CT scans it is meant a 3D integer matrix corresponding to a X-Y-Z meshed volume with uniform mesh size for each co-ordinate direction (not necessarily the same for all the three directions) where each matrix element is the identification number of a zone or material. That means that users need software tools in order to translate the "grey shades" coming from a tomographic facility into a particular material zone distribution. BOT3P3.0 can easily manage all the overlapping situations among different material zones by means of the priority concept. This is nothing else than an integer parameter associated to all material zones to be input to BOT3P. The code attributes the mesh the material identification number of the zone with the highest priority whenever overlapping occurs. This extends further flexibility and power of the tool to define the input geometry in addition to the combinatorial geometry approach used in the codes. This new feature of BOT3P makes it possible to re-use existing DORT/TORT input files to generate a new geometry.
• •When users require X-Y-Z TORT/THREEDANT mesh grids to be generated, BOT3P Version 3.0 produces also a geometrical input file for MCNP. It consists of as many parallelepiped cells as the TORT bodies are, without any overlapping among one another and filling up the finite TORT/THREEDANT X-Y-Z domain. BOT3P adds a void cell to define the universe outside this finite domain. The plane equations (PX, PY, PZ MCNP mnemonic input cards) defining all the cell boundaries are at the same time prepared by the code. BOT3P reports in commented cards the cell list related to each material, a material volume summary and the cells related to each uniform volumetric source distribution, if any.
• •BOT3P3.0 can be a useful analysis tool both for reactor and medical applications. 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.
  
  

5. METHOD OF SOLUTION

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 characterize the geometric scheme at the basis of the TORT/THREEDANT geometric and material model are read, sorted and all stored if different from the neighboring ones more than 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 geometric shapes in space thanks to the combinatorial geometry among volumes existing in GGTM. Bodies are then generated (only for TORT) by aggregating neighboring cells belonging to the same zones, taking care to fill up all the geometric 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 don't 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.

6. RESTRICTIONS OR LIMITATIONS

Only a continuos space mesh grid can be generated by GGDM and GGTM and input to DDM, DTM2, DTM3 and RVARSCL. It must be remembered that DDM, DTM2 and DTM3, if used in combination with DORT/TORT geometric 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 geometric models, users are advised not to generate more then 2 or 3 frames in the same DTM3 run in order to avoid too big metafiles and postscript files

7. TYPICAL RUNNING TIME

Central processor unit (CPU) time is roughly proportional to the number of cells the 2D/3D models created by GGDM/GGTM consists 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 be very 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 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. BPT3P Version 2 is a little slower than Version 1.0, since it must prepare the TWODANT/THREEDANT model in addition to the DORT/TORT mode.

8. COMPUTER HARDWARE REQUIREMENTS

BOT3P programs run on DEC Alpha, Sun, IBM RS/6000 and PC Linux systems.

9. COMPUTER SOFTWARE REQUIREMENTS

BOT3P has been tested under several Unix workstations. BOT3P2.0 has NOT been implemented under Windows. Executables that were created at RSICC on a Pentium computer under RedHat Linux 7 with the Portland Group, Inc. Version 4.0-2 compiler are included. A Fortran 77 compiler is required to compile the codes on all other computers. The RSCORS, Sandia National Laboratory subroutine library of graphical primitives, is required to install and run BOT. RSCORS is distributed with the CCC-650/DOORS3.2 and DOORS3.2a packages. RSICC tested BOT3P under the following systems:

AMD Athlon running RedHat Linux 7.3 with Portland Group, Inc. 4.0-2 compiler

DEC alpha - Digital UNIX V40.D (Rev. 878) - Compaq Fortran Compiler V5.5

IBM RS/6000 - AIX 4.3.3 system - IBM XL Fortran for AIX Version 7.1

Sun SparcStation - Sun OS 5.6 - Sun WorkShop Compilers 5.0 98/12/15 FORTRAN 77 5.0

10. REFERENCES

a) included in documentation:

R. ORSI, "BOT3P Version 3.0: The ENEA Balogna Pre-Processors of the DORT, TORT, TWODANT, THREEDANT and MCNP Transport Codes and Post-Processors of DORT and TORT," FIS-P129-001 (2002).

b) background information:

W.A. Rhoades, R.L. Childs, RSICC Computer Code Collection CCC-650, "DOORS-3.2, One, Two- and Three-Dimensional Discrete Ordinates Neutron/Photon Transport Code System,"

W.A. Rhoades and D. B. Simpson, "The TORT Three-Dimensional Discrete Ordinates Neutron/Photon Transport Code," ORNL/TM-13221 (October 1997).

S.L. Thompson, "The RSCORS Graphics System," SAND99-XXXX Sandia National Laboratory Working Document (October 19, 1991).

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).

"MCNP TM - A General Monte Carlo N-Particle Transport Code. Version 4C," LA-1309-M, Los Alamos National Laboratory, Los Alamos, New Mexico, USA (March 2000).

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, "BOT3P Version 2.0: The ENEA Nuclear Data Centre Pre/Post-Processors of the DORT, TORT , TWODANT and THREEDANT Deterministic Transport Codes", FS-P127-001, ENEA-Bologna, Italy (2002).

E. E. Lewis (NW-University), M. A. Smith & N. Tsoulfanidis (U-Missouri), G. Palmiotti, T. A. Taiwo & R. N. Blomquist (ANL): "Specification for Deterministic 2-D/3-D MOX fuel assembly transport calculations without spatial homogenisation (C5G7 MOX)", Expert Group on 3-D Radiation Transport Benchmarks Benchmark, NEA/NSC/DOC(2001)4, Organization for Economic Cooperation and Development Nuclear Energy Agency, Paris, France, (March 2001).

"Expert Group on 3-D Radiation Transport Benchmarks. Summary of meeting on C5G7 Mox Benchmark", Hollywood, Florida, USA, June 11, 2002, NEA/NSC/DOC(2002)13.

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, France (April 12-14, 1999).

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 22-24, 2000).

11. CONTENTS OF CODE PACKAGE

The package is transmitted as a GNU compressed Unix tar file on a CD. The tar file contains the source files for all programs in the auxiliary codes list, linux executables, test cases, implementation instructions, procedures, description of sample problem cases, and documentation.

12. DATE OF ABSTRACT

October 2003.

KEYWORDS: PLOTTING; NEUTRON; GAMMA-RAY; CYLINDRICAL GEOMETRY; COMPLEX GEOMETRY; MESH GENERATION; WORKSTATION