SIMULATE-3K is an advanced, two-group nodal code for transient analysis of both PWRs and BWRs. SIMULATE-3K delivers neutronic and thermal-hydraulic analysis with licensing-grade accuracy over a wide range of dynamic applications.

High-Fidelity Core Model

SIMULATE-3K is built on the solid foundation of SIMULATE, the leading nodal reactor analysis code.

Detailed Thermal-Hydraulics

Each fuel assembly in the core is explicitly represented in the core thermal-hydraulics.

Reliable Safety Analysis

SIMULATE-3K is licensed by safety authorities around the world for several transient applications.

High-Fidelity Core Model: Proven Neutronic Analysis

SIMULATE-3K leverages the power of SIMULATE, the industry standard in nodal reactor analysis. Including cutting-edge neutronic methods and advanced engineering features, SIMULATE-3K delivers unparalleled fidelity with production-level run times.

SIMULATE-3K solves the transient three-dimensional, two-group neutron diffusion equations, including a six-group model for delayed neutron precursors. Intra-nodal flux and power distributions within each node are used to compute the power, fuel temperatures, and enthalpies for every axial level of every fuel pin in the core during transients.

Detailed Thermal-Hydraulics: Models for BWRs and PWRs

With a robust neutronics engine and advanced thermal hydraulic capabilities, SIMULATE-3K is well-suited for transients with a strong neutronic/thermal-hydraulic coupling.

BWR Applications

For BWR operational transients, vessel and steam line models are capable of simulating acoustic effects in the steam line due to sudden valve closures or openings.

SIMULATE-3K can provide licensing-grade support for analyzing BWR-specific safety analyses and fast anticipated operational occurrences where the primary acceptance criteria are fuel rod integrity such as:

  • Reactor stability
  • Reactivity insertion accidents (RIA) like dropped rods and inadvertent bank withdrawals
  • Pressurizations created in the steam dome and/or the steam lines with valve control and actuation
  • Coolant inventory or flow change transients using the two groups of pumps
  • Coolant temperature changes and instabilities that occur during a flow decrease/temperature events

PWR Applications

SIMULATE-3K can provide licensing-grade support for analyzing PWR-specific safety analyses, such as:

  • Reactivity insertion accidents (RIA) like ejected rods and inadvertent bank withdrawals
  • Dropped rods
  • Boron dilution accidents

Reliable Safety Analysis: Address Emerging Issues

SIMULATE-3K seamlessly links to SIMULATE, making it the perfect tool for the study of operational transients typically analyzed on a cycle-specific basis. Core designers simply generate the proposed core model, and direct SIMULATE-3K to evaluate the prescribed set of transients as part of the core reload design licensing process.

SIMULATE-3K has been successfully used by clients for stability analysis, reactivity insertion analysis, dynamic rod worth calculations, and past operational events. SIMULATE-3K is capable of evaluating margin to thermal limits during plant transients, and can help operators address regulatory issues like pin enthalpy and delta-CPR.

SIMULATE-3K has been coupled with system codes like RELAP and RETRAN. The powerful neutronics engine inside SIMULATE-3K guarantees a high-fidelity, 3D core neutronic solution in whole-plant transient simulations.

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Mehdi Asgari

Manager Marketing & Business Development

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