Numerical simulation of flow and heat transfer between thermal column lead slab and core edge surfaces in a pool-type research reactor and enhancement of its cooling condition

In pool-type research reactors, utilizing thermal column irradiation facilities through the fission process in the core, gamma rays are produced and absorbed by lead slab as a gamma rays shield of thermal column. Consequently, heat is generated in the lead slab surface which induces flow by the thermal buoyancy force. In the present work, 3D, CFD simulation of flow and heat transfer in a channel, formed by the thermal column and core edge, is considered. The aim is to obtain the temperature distribution on the lead surface and also a solution to prevent boiling, which may occur on the lead surface. It is observed that the hot spot on the lead surface exceeds the boiling point in natural convection mechanism. Therefore, the grid plate is extended underneath the channel so that water can flow through the channel and exit to the plenum causing forced convection to be established as an effective way to eliminate the boiling occurrence.