Thermal hydraulic analysis of a tubular fuel assembly in the normal operating condition of Tehran Research Reactor core

Abstract

The purpose of this paper is to investigate the possibility of using tubular fuel assemblies in Tehran Research Reactor (TRR) from the thermal hydraulic perspective. Tubular fuels have been used successfully in many Russian model research reactors in recent decades. The most important advantages of this fuel are higher neutron flux, more reactivity and less fuel loading compared to the current plate fuels. In this study, by selecting a tubular fuel assembly of IRT-4M type that is more geometrically compatible with the geometry and dimensions of the core grid plate, we modeled it using the Fluent software and also the RELAP5/Mod3.2 code. The thermal hydraulic parameters of this assembly have been calculated under the operating conditions of current MTR fuel. The results of the calculations showed that the maximum clad temperature in both calculation tools is sufficiently lower than 105°C, which indicates that without changing the current flow rate of the core, the heat produced in the tubular fuel can be well removed. Moreover, the maximum fuel temperature in tubular fuel is about 10°C lower than the maximum fuel temperature in the current standard fuel element, which is another advantage for this fuel type.

Keywords

• tubular fuel
• tehran research reactor
• thermal hydraulic
• fluent software
• relap5 code