MNRSIM: A Research and Training Model of the McMaster Nuclear Reactor

User Manual

Thermal Hydraulics Loop 1

The primary thermal hydraulics loop models the fluid flow between the pool and the hold up tank. Most of the valves are operational, the pump can be turned on and off, and the pool and HUT tank levels can be altered by dragging the water levels up and down.

Each time a control is changed the steady state pressures and flow rates are recomputed. To watch the model run click on the SIM button in the upper right corner. The SIM button will change to a PAUSE button while the simulation is running.

Under the schematic there is a simple process graph which shows the main modules which are related to the current module. This can be thought of as a submenu. The core heat transfer module is started from the process graph for the thermal hydraulics loop.

Core Heat Transfer Module

This window allows the user to examine the heat profiles that are generated in individual plates. Since this can be a very demanding calculation at the bottom of the screen several approximations are available. The plate approximation computes the heat distribution for a single fuel plate, the assembly approximation calculates all of the plates in the hottest assembly, and the core approximation computes heat profiles for each assembly in the core. The core approximation is largely redundant at this point, but we plan to allow the flow rates for each channel in each assembly to be modified.

The graph to the right of the panel shows the temperature distribution of the fluid. To change either the Z divisions or the X divisions the timeline must be reset to zero. The vertical slider selects the cross section depth to be used in the fuel plate temperature distribution.

Since the module is computationally demanding it can be unlinked from the main simulation by unchecking the HTS1-Link box. With this box unchecked the user can run this module with the SIM button without starting up the thermal hydraulic simulation. Likewise if the HTS1-Link button is unchecked starting the thermal hydraulic simulation will not invoke the heat transfer module.