RETRAN/MINET composite code documentation

The RETRAN/MINET Composite Code, based on RETRAN O2 MOD 4 and MINET Version 1.10, is described. The objective in developing RETRAN/MINET was to extend the degree to which complex thermal-hydraulic systems can be analyzed, while providing the capability to use detailed RETRAN modeling of the reactor and other components, where needed. The MINET Code was originally developed for the analysis of complex balance of plant (BOP) thermal-hydraulic systems and already serves that purpose in support of RAMONA-3B for BWR analyses and SSC for LMR analyses. The project was sponsored by the Empire State Electric Energy Research Corporation (ESEERCO), with computer and engineering support provided by the New York Power Authority (NYPA). A modular'' interfacing technique was utilized, in that there is very little change in the programming of either individual code, except that the MINET driver program is discarded and major sub-drivers are called from the appropriate locations within RETRAN. One new common block was added to act as a buffer between the data structures for each code. During execution, boundary conditions at the interface are exchanged via this buffer, and each code sees only the normal'' boundary conditions -- although some of the user's boundary conditions are overwritten atmore » interface boundaries. A major advantage of this approach is that the interface is very localized, which is helpful for testing and makes upgrading to newer versions of RETRAN and MINET relatively straightforward. Information regarding composite code modeling, programming and utilization is provided. Sample input and output are also included. 19 figs., 7 tabs.« less