Numerical Simulation of Pressure Loss and Heat Transfer in Road Bundle Fuel Assembly with Spacer Grids

Abstract

The spacer grids in nuclear fuel assembly are one of the equipments that affect the fluid flow distribution with the creation of turbulence and driven fluid flow in a sub-channel. In the present paper, the fuel bundle in the VVER-440 nuclear reactor that contains 60 fuel rods and 4 spacer grids has been simulated and solved by a numerical method. Three turbulent models were used. The results showed that using spacer grids over the fuel bundle led to an increase in the heat transfer coefficients. However, these grids increase the pressure drop. The results of this research can be used to design and manufacture the fuel assembly and obtain the relevant thermo hydraulic parameters to optimize the heat transfer of fuel rods.

Keywords

• spacer grid
• fuel assembly
• thermal-hydraulic parameters