S3R

Licensing-Grade Core Model: Real-Time Performance

S3R provides high-fidelity core modeling with real-time response by using the same physics methods found in SIMULATE, the modeling tool used by engineers for core design and analysis.

S3R acquires all the data needed for the simulator directly from the output of SIMULATE, with no intermediate steps or linking tools. No tuning or normalization is required to get accurate results.

S3R executes with a fixed iteration count to provide a stable and repeatable convergence, usually in under 250ms. S3R also includes a “fast-time” option to simulate core behavior at up to 1000x real-time for fission product and decay heat conditions. Fission products like xenon, iodine, promethium, and samarium can be forced into equilibrium at any time and decay heat can be increased if needed.

Seamless Data Transfer: Support Just-in-Time Training

Each time the core model is updated by the core designers, the S3R simulator can be easily updated with the same data. Since S3R reads the same restart and library files used by SIMULATE, updating the simulator does not significantly increase the workload on the core analysis (or fuels) organization.

S3R also maintains a set of predefined initial conditions that can be reused from cycle-to-cycle, without having to maneuver the simulator each time. The cycle conversion algorithm converts all equilibrium initial conditions to the new cycle, drastically reducing simulator maintenance time.

Various core “lives” can co-exist in a single cycle of operating history to analyze the effects of unexpected operational events. These alternate histories can be loaded from the SIMULATE core model and installed on the S3R simulator in a matter of minutes to support just-in-time training activities.

Plug-and-Play: Integrates into any Plant Simulator

S3R easily integrates into most common simulators. It has been successfully integrated with the executive systems, instructor stations, and thermal-hydraulic models of vendors like CORYS, GSE Systems, WSC Inc. and L-3 MAPPS.

S3R perform as a module under the control of an executive system and responds to instructor station actions like initialize/run/freeze, snapshot/backtrack, and fast-time.

The S3R module resides in an interface wrapper that communicates with the database. The inbound portion of the wrapper routine gathers all the data needed to take a step (rod position, T/H variables, etc). The outbound portion of the wrapper scatters all the S3R results (power, flux, detectors, etc.) back into the database.

Credible Operator Training: Meets All Regulatory Requirements

Since the S3R core modeling data comes directly from the same cycle-specific CASMO/SIMULATE model used by core designers and engineers, it maintains high-fidelity with the actual operation of the reactor. S3R models each fuel assembly and all instrumentation explicitly in 3D, allowing operators to train on a model that behaves exactly like the real plant.

Studsvik has over 20 years of experience in the modeling of commercial nuclear reactors. Studsvik software has been licensed for many applications by the United States Nuclear Regulatory Commission and other international regulatory authorities.

S3R has been installed at more than 50 PWR and BWR sites in several countries and conforms to the modern performance expectations specified in ANSI 3.5, INPO SOER 96/02, and 10 CFR 55.46.