Document Type


Publication Date


First page number:


Last page number:



Various fuel cycle concepts for plutonium incineration in existing PWR loaded with Inert Matrix Fuel (IMF), in which uranium is replaced by neutron-transparent inert matrix material, are currently under investigation at BGU. Some of the studied designs include ZrO2-based IMF with annular fuel geometry and ZrO2-MgO based IMF with the relative amount of MgO varied from 30v/o to 70v/o. These concepts are analyzed via detailed three-dimensional full core simulation of existing PWR including thermal-hydraulic feedback. The whole core simulations are carried out with the SILWER code. The SILWER code, which is a part of the ELCOS1 system, performs three-dimensional neutronic calculations with thermal-hydraulic feedbacks of the full reactor core. Ability of the SILWER code to simulate the operation of a modern PWR loaded with all-UO2 fuel was demonstrated in the past2. However, two important limitations of the SILWER code with regards to the IMF analysis should be noted.

1. During fuel temperature calculations, SILWER thermal-hydraulic module employs the thermal conductivity of UO2. These data cannot be applied to IMF because the thermal conductivity of IMF differ from UO2 and depends on inert matrix material composition (Fig. 1).

2. Thermal-hydraulic module performs fuel temperature calculations assuming solid fuel pellet geometry even for the annular fuel. Thus, in order to adapt the SILWER code for simulation of PWR core loaded with IMF several modifications to the SILWER code were made.


Magnesium oxide; Mixed oxide fuels (Nuclear engineering); Nuclear fuel elements; Nuclear fuels; Plutonium; Radioactive wastes — Incineration; Solid oxide fuel cells; Zirconium oxide


Nuclear | Nuclear Engineering | Oil, Gas, and Energy




3rd Progress Report