Visualization Test for Flow Field of Bundles with Grid Spacers

This paper studied the effect of AFA-2G 5x5 grid spacers on flow used in visualization test. The dye method was used to study the mixture effect of mixing vanes. Tracing particle method was used to observe 3D-flow field in rod bundles. 2D Laser Doppler Velocimeter （LDV） measured axial and lateral velocities of up-flow and down-flow of grid spacers. Pressure drops were also measured to estimate loss coefficients for the grid spacer and friction factors for rod bundles, and obtained formulation for loss coefficients and Reynolds and formulation for friction factors and Reynolds.