1. NAME AND TITLE

COGAP: Nuclear Power Plant Containment Hydrogen Control System Evaluation Code.

2. CONTRIBUTORS

Los Alamos National Laboratory, New Mexico.

Exelon Nuclear, Kennett Square, Pennsylvania.

3. CODING LANGUAGE AND COMPUTER

Fortran; CDC or Intel PC under Windows 95/98/2000 (P00375MNYCP01).

4. NATURE OF PROBLEM SOLVED

COGAP evaluates nuclear power plant containment hydrogen control systems by determining the node (compartment) concentrations of hydrogen, oxygen, nitrogen, and steam, assumed to be ideal gases. The nodes are assumed to behomogeneous and in chemical equilibrium, that is, lumped-parameter nodes. Effects accounted for include: reaction of zirconium and water; radiolysis of core and sump water; corrosion of zinc, aluminum, and copper; recirculation between compartments; hydrogen recombiners; purging; nitrogen addition; and atmospheric steam. Controls are available to determine when options are initiated, e.g., hydrogen recombiners can be started when the hydrogen concentration reaches a user-specified value or after a user-specified time.

5. METHOD OF SOLUTION

Nodal gas content accounting is determined explicitly, based on addition, removal, or transport of constituents resulting from the effects considered.

6. RESTRICTIONS OR LIMITATIONS

Maxima of 20 hydrogen recombiner connections, 20 connections between compartments for recirculation, 10 corrosion surfaces, and 5 compartments.

7. TYPICAL RUNNING TIME

The sample problem, which includes two cases, required about 6 CP seconds on a CDC7600 and 16 CP seconds on a CDC CYBER175. The sample problem requires just a few seconds on a Micron P3 650 mHz 128MB Ram running Windows 2000.

8. COMPUTER HARDWARE REQUIREMENTS

COGAP runs on Intel personal computers. 55,000 (octal) words of memory were required for CDC7600 execution; the CDC CYBER175 required 36,000 (octal) words.

9. COMPUTER SOFTWARE REQUIREMENTS

The CDC version was developed under SCOPE 2.1 (CDC7600); NOS 1.4 (CDC CYBER175). The included PC executables were created on a Dell PII-366 Laptop running windows 2000 using the Compaq Visual Fortran Version 6.5. The PC code runs under Windows 95, 98 or Windows 2000.

10. REFERENCE

R.G. Gido, "COGAP: A Nuclear Power Plant Containment Hydrogen Control System Evaluation Code," NUREG/CR-2847 (LA-9459- MS) (January 1983).

11. CONTENTS OF CODE PACKAGE

Included in the package is one CD which includes the source, readme files, PC executable, test problems, output, and referenced document.

12. DATE OF ABSTRACT

Abstract first distributed February 1983 by ESTSC. The sample problem was executed by NESC December 1982 on a CDC CYBER175. The package was transferred to ESTSC and then to RSICC in December 1998. The PC version was added to the package in January 2003.

KEYWORDS: CONTAINMENT; HYDROGEN