RSICC CODE PACKAGE PSR-543

 

1.  NAME AND TITLE

ADEFTA 4.0:     Atomic Densities for Transport Analysis Script.

 

2.  CONTRIBUTORS

ENEA/FPN-FISNUC (Nuclear Data Centre), Bologna, Italy, through the OECD Nuclear Energy Agency Data Bank, Issy-Les Molineaux, France.

 

3.  CODING LANGUAGE AND COMPUTER

Bourne Shell; Workstation or PC (P00543MNYCP00).

 

4.  NATURE OF PROBLEM SOLVED

ADEFTA is a script file for any UNIX/Linux platform that uses only Bourne shell commands and the "awk" UNIX (and Linux) utility in order to calculate the atomic densities related to any compositional model for transport analysis. The output produced by ADEFTA can be useful for applications with many transport codes. However ADEFTA is particularly addressed to users of both the GIP code, which prepares macroscopic cross-sections for the DORT and TORT deterministic transport codes (CCC-650), and the Monte-Carlo MCNP codes (CCC-730). NEADB distributes ADEFTA 4.0 with package identifier NEA-1708/05.

 

5.  METHOD OF SOLUTION

ADEFTA output normally consists of two files: the former for "general use" since the atomic density (atom/(barn*cm)) for each isotope contained in a material mixture of an input compositional model is reported together with the corresponding atomic fraction in the material or mixture, the latter more directly addressed to MCNP and only containing the atomic fractions. A third output file (optional) can be produced by ADEFTA: this is a partial input file to GIP. It is denoted partial because users must input by themselves the array containing the cross sections for all the nuclides of the complete working library (14** data entries). This is a simple editor operation and is the only one to be required of users in order to have a complete GIP input formally ready to be run. Users may, of course, change the default values assigned to some data entries by ADEFTA according to their own needs before really running GIP.

              ADEFTA needs the following input files:

            • the data base file with atomic weights and isotopic abundances distributed with the script file);

            • the input compositional file related to the problem to be dealt with;

            • the FIDO format library index file (optional; required only if the generation of a partial input file to GIP is also to be produced).

Users can easily define in the input compositional file materials consisting of various natural elements or expressed by one or more chemical formulae (for example UO2, H2O, B2O3), each component (natural element or formula) with its own weight fraction and with the possibility to define a particular enrichment of the related isotopes. In such a case users must refer in the ADEFTA input compositional file directly to the precise isotopes instead of the natural elements.   

  When defining a material, users can decide, according to the input modalities of ADEFTA, if they want to calculate the atomic densities of the natural elements composing the material or to let ADEFTA automatically split them into the single related isotopes. They can also define mixtures, particularly oriented to produce the input file for GIP, in order to calculate the atomic densities of a homogenized mixture consisting of different materials, each of them with its own volumetric fraction (for example, as in a fuel cell). It is also possible to define a void region in a mixture with its own volumetric fraction.

ADEFTA sums the density contributions of the same isotopes with different origins that are present in a material or mixture. However it is also possible to distinguish such contributions. For instance, let us suppose that our mixture consists of a volume fraction of water and of another volume fraction of a material containing also hydrogen. ADEFTA allows users not to join hydrogen density coming from water with that from the other material. This option is indispensable when our working library contains different processed files for the same natural element or isotope and we want to refer to a specific processed file of our working library, such as, for example:  H1 for free 1H or H1-H2O for 1H in water (thermal application).

 

6.  RESTRICTIONS OR LIMITATIONS

None noted.

 

7.  TYPICAL RUNNING TIME

ADEFTA 4.0 is interactive. All test cases ran in seconds on a Pentium PC.

 

8.  COMPUTER HARDWARE REQUIREMENTS

The ADEFTA 4.0 script runs on Unix workstations or Linux based personal computers and consumes less than 2 Mb of disk space.

 

9.  COMPUTER SOFTWARE REQUIREMENTS

ADEFTA can be run in the Bourne shell on Unix or Linux operating systems and can also be run under Cygwin on Windows-based personal computers. The DOORS 3.2a and the MCNP code packages are available as separate packages from either RSICC or the NEA Data Bank.

 

10. REFERENCE

R. Orsi: “ADEFTA version 4.0: A Program to Calculate the Atomic Densities of a Compositional Model for Transport Analysis,” FPN-P9H6-004 (April 2007).

 

11. CONTENTS OF CODE PACKAGE

The package is transmitted on a CD in a Unix tar file which includes the referenced document listed above, the script, data files and test cases.

 

12. DATE OF ABSTRACT

November 2007.

 

KEYWORDS:   INPUT GENERATOR; ISOTOPIC DENSITIES