A three-dimensional improved quasi-static core model for nuclear reactor control room simulators

With the availability of powerful modern mini-computers, more sophisticated and accurate modeling is now expected of nuclear reactor control room simulators. Today, such simulators must model a wide range of operational and accident conditions which place great demands on computers and models. The core model in Combustion Engineering Calvert Cliffs I full scope control room simulator illustrates this trend. It features a full core, three-dimensional space-time neutronic and thermal-hydraulic model and runs on one of the simulator's Perkin Elmer 3244 computers using a small fraction of that machine's computing capability. The feasibility of using 3-D kinetics for real time simulation was demonstrated in Reference Addition of thermal-hydraulics and a new approach to the improved quasi-static method (IQSM) are described here. The resulting model has successfully simulated operational and accident transients with a speed of 40 to 80 msec per reactor second. Thus, it fits easily into the real time requirements of the integrated simulator