Transient & Safety Analysis

Studsvik transient & safety analysis services have been performed for clients needing stability analysis, transient CPR analysis, reactivity insertion analysis, dynamic rod worth calculations, anticipated operational occurrences (AOO), and post-operational event analysis and have been licensed by safety authorities for several transient applications.

Changes to physical conditions at nuclear power plants such as power uprates, turbine and system upgrades, instrumentation and control upgrades, and new chemical injection systems require the plant operator to update the Safety Analysis Report (SAR) to reflect state of the art codes and methods for transient analysis. Studsvik can help build and qualify transient models for use in cycle-specific transient analyses of special events and design basis accidents or for stability predictions.

Studsvik can perform safety analysis calculations to address reactivity insertion transients initiated by unintentional control rod motions, such as control rod drop or rod withdrawal error. Detailed technical reports are produced that will constitute reference documents for the SAR. Commonly analyzed events range from expected operational transients to design basis accidents.

Extended Transient Analysis Outside the Core

Studsvik’s transient nodal code, SIMULATE-3K, is used for the 3D transient analysis, utilizing features like extensive editing of pin-by-pin temperatures and enthalpy. The fuel heat transfer package models boiling crisis and allows for CPR evaluation for all the fuel elements in the core. For more detailed simulation of plant behavior, SIMULATE-3K can be coupled to system codes like RELAP or RETRAN and other balance-of-plant models.