1. NAME AND TITLE

PADLOC: A One-Dimensional, Time-Dependent Program for Calculating Coolant and Plateout Fission Product Concentrations in a Network of Pipes.

2. CONTRIBUTOR

General Atomic Company, San Diego, California.

3. CODING LANGUAGE AND COMPUTER

Fortran IV; UNIVAC.

4. NATURE OF PROBLEM SOLVED

The one-dimensional computer program PADLOC is designed to analyze steady-state and time-dependent plateout of fission products in an arbitrary network of pipes. The problem solved is one of mass transport of impurities in a fluid, including the effects of sources in the fluid and in the plateout surfaces, convection along the flow paths, decay, adsorption on surfaces (plateout), and desorption from surfaces. These phenomena are governed by a system of coupled, nonlinear partial differential equations.

5. METHOD OF SOLUTION

The solution is achieved by a) linearizing the equations about an approximate solution, employing a Newton-Raphson iteration technique, b) employing a finite-difference solution method with an implicit time integration, and c) employing a substructuring technique to logically organize the systems of equations for an arbitrary flow network.

6. RESTRICTIONS OR LIMITATIONS

None noted.

7. TYPICAL RUNNING TIME

No study has been made by RSIC of typical running times for PADLOC.

8. COMPUTER HARDWARE REQUIREMENTS

The code is operable on the UNIVAC computer.

9. COMPUTER SOFTWARE REQUIREMENTS

A Fortran IV compiler is required.

10. REFERENCE

W. W. Hudritsch and P. D. Smith, "PADLOC, A One-Dimensional Computer Program for Calculating Coolant and Plateout Fission Product Concentrations," GA-A1401 (November 1977).

11. CONTENTS OF CODE PACKAGE

Included are the referenced document and one (1.2MB) DOS diskette which contains the source code.

12. DATE OF ABSTRACT

January 1982.