Effect of Vanes Angles on the Flow around Fuel Rods and the Induced Vibrations by Analyzing Solid-Fluid Interaction

Document Type : Original Article

Authors

• Mansour Talebi ¹
• Siamak Nabati ²

¹ Nuclear Science and Technology Research Institute

² Islamic Azad University, Isfahan, Iran

10.22067/jacsm.2021.71640.1046

Abstract

In the nuclear fuel assembly, the mixing vanes are solid components which are attached to the spacer grid. These vanes would increase heat transfer rate from the fuel wall. The force induced by flow may expose the vanes to excessive stress and bending, which in turn, it impairs the mixing vanes. In order to improve the heat transfer rate and decrease the vibrational forces, vanes are usually positioned at a certain angle regarding to the flow axis. This study investigates displacement of vanes in three angles of 65, 70 and 75 degrees for a specific geometry using the fluid-solid interaction method. First, the fluid flow is solved using a Finite Volume Method (FVM) solver and the forces exposed by the flow to the vanes are estimated. Next, the displacement of the vanes due to the applied forces is calculated by the Finite Element Method (FEM). Comparison between calculated pressure drop in this study and experimental result show a difference less than 10%. The maximum pressure drop is occurred when the vanes have 65° angle. The most turbulence intensity is obtained at the angle of 75°. Also, according to the frequency estimation, it was observed that with increasing frequency the displacement's amplitude would decrease.

Keywords

• Mixing Vanes
• Fuel Assembly
• Fluid Solid Interaction
• Induced vibrations

Main Subjects

• Fluid mechanics

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