**RSICC CODE PACKAGE CCC-674**

**1. NAME AND TITLE**

MTR_PC V2.6: Modular Code System for Neutronics, Thermalhydraulics and Shielding Calculations.

**2. CONTRIBUTOR**

INVAP SE, Bariloche, Rio Negro, Argentina.

**3. CODING LANGUAGE AND COMPUTER**

Fortran 77; IBM PC (C00674PC38600).

**4. NATURE OF PROBLEM SOLVED**

MTR_PC is a modular code system which can perform neutronic, thermalhydraulic and shielding calculations for MTR-type reactors on personal computers. A complete set of programs performs calculations, manages data and plots results. MTR_PC offers the following possibilities:

- Steady-state neutronic and thermalhydraulic studies.

- Time and burn-up dependent calculations.

- Perturbation calculations (kinetic parameters).

- Fuel management.

- Transient and accident calculations.

- Calculations for production, decay and processing of radioactive materials.

- Shielding calculations for neutrons and gamma radiations.

**5. METHOD OF SOLUTION**

The modular design allows the user to choose a particular set of programs and easily change or add other codes. From a set of menus, the user may choose a specific task by means of a letter (hot key), cursor or mouse positioning. MTR_PC includes a driver, several well known programs plus cross section libraries.

**6. RESTRICTIONS OR LIMITATIONS**

Restrictions are noted in program documentation.

**7. TYPICAL RUNNING TIME**

Neutronic: Few minutes to several hours depending on the size of the calculated system.

Thermalhydraulic: Few seconds for steady state; few hours for large transient calculations.

Shielding: Few minutes to several hours depending on the size of the calculated system.

**8. COMPUTER HARDWARE REQUIREMENTS**

The system runs on PC 386, PC 486 or Pentium personal computers.

**9. COMPUTER SOFTWARE REQUIREMENTS**

The calculational codes were compiled with Lahey F77L-EM/32 V 5.2, and the driver and post processors were compiled with Microsoft v5.1. Executables which can be run under either DOS 6 or in a MS-DOS box of Windows95 are included in the package.

**10. REFERENCES**

** **E. A. Villarino**, **"Abstract" (1996).

E. A. Villarino, "MTR_PC v2.6: Neutronic, Thermalhydraulic and Shielding Calculations on Personal Computers" (July 1996).

**11. CONTENTS OF CODE PACKAGE**

Included are the referenced document and 11 diskettes which contain compressed (PKZIP) DOS files. An interactive install procedure will expand and install documentation files, source files, cross section libraries, and executables.

**12. DATE OF ABSTRACT**

June 1999.

** KEYWORDS:** CROSS SECTIONS; ISOTOPE INVENTORY; REACTOR ACCIDENTS;
NEUTRONS; CELL CALCULATION; PERTURBATION THEORY;
REACTOR PHYSICS; DISCRETE ORDINATES; ONE-DIMENSION; TWO-DIMENSIONS