Advanced Reactor Simulations

Scope of Simulation

The simulation will include operational and transient behaviour for advanced reactor types of PWRs, BWRs and PHWRs in the 600 MWe range. For PWRs, plants of vertical inverted U-bend steam generators as those designed in the west and of horizontal steam generators designed by the former Soviet Union will be covered. “Advanced” means the generation of nuclear power plants currrently under design or construction which use the culmination of past design, development and operating experience and incorporate evolutionary improvements and/or non-conventional changes.

For PWRs and PHWRs, the evolutionary improvements include lower power density in the core and upgraded reliability for the feedwater and emergency coolant supply. A non-conventional design has used completely passive safety systems. For BWRs with passive safety systems, the above advanced plant types will not be covered. In particular, differences between the conventional (engineered) safety designs and passive safety features in their response to a design basis accident willl be demonstrated.

The software will use commonly available MS-DOS and compatible Windows environment for Intel microprocessor-based personal computers. The simulation program will be a desk-top version that can be run on a PC with a Pentium configuration.

Training Functions

By using the simulation software, in conduction with the Training Material, the following areas and reactor characteristics are expected to be covered:

1. Principle Types of Water Cooled Reactors:
   Several Advanced Water-cooled Reactor designs in the 600 MWe range will be covered. For PWRs, plants of vertical inverted U-bend steam generators as those designed in the west and of horizontal steam generators designed by the former Soviet Union will be covered. Differences between the conventional plants and PWR with passive safety features in their response to a design basis accident will be demonstrated.
2. Characteristics and Capabilities of Each Reactor Type:
   The characteristics of each of these reactor types will be demonstrated by their corresponding simulation models. The characteristics will include:
   • neutronics with reactivity control by rods and feedback
   • heat transfer through the fuel cladding into the coolant
   • reactor coolant thermal-hydraulics
   • principle of the control systems
3. Characteristics of Plant Components and Systems to be simulated will include:
   • Reactor Core
   • Reactor Coolant System
   • Emergency Core Cooling Systems (ECCS)
   • Containment
   • Control Systems
4. Simulation will be real time. For slow transients, the ability to accelerate the simulation is included (up to 20 times real time).
5. Simulations will include all normal and abnormal design basis conditions relevant to the reactor type. This will include:
   • Normal conditions
   • Startup and shutdown
   • Power maneuvering
   • Abnormal Transients
   • Operational transients
   • Accident analyses
   • "Unknown" Event Diagnosis (Symptom-oriented emergency response)
   • Sensitivity Studies: Discussion of the overall transient as a result of key plant parameter change and/or operator action
6. The software of the simulator will be written in FORTRAN, graphics software tools will be used.
7. Simulator/operator interface will be user friendly. To facilitate control actions and diagnostics by the operator, virtual control panels that are similar to the real ones used in the simulated system will be used.

© 2007 Micro-simulation Technology