Effect of intake geometry on the velocity distribution upstream of intakes

The effect of intake geometry on the velocity distributions upstream of intakes receiving water from a dead-end channel was compared both theoretically and numerically. In theoretical analysis, the available potential flow solution was used to find the velocity distribution in the vicinity of the intake structures. For numerical investigation, the computational fluid dynamics model was first calibrated with the available experimental data for circular cross-section pipe intake, and then the analyses of various intake types were performed with and without flow boundary effects due to channel bottom and sidewalls. Theoretical and CFD results showed that the effect of the intake geometry on the velocity distribution in the vicinity of the intakes is large, but this effect disappears as the distance from the intake increases. For rectangular intakes with high aspect ratios, iso-velocity contours become different than that of the pipe intake while the behaviors of the square, and triangular intakes are similar to the pipe intake. The flow boundary effects spoil the shape of the iso-velocity contours and generate larger velocities in the region away from the boundaries compared to the case with no boundary effects. The agreement between numerical and theoretical results was found to be satisfactory.

Automated summary

This study compared the effect of intake geometry on the velocity distributions upstream of intakes receiving water from a dead-end channel using both theoretical and numerical analyses. The results showed that intake geometry had a significant impact on the velocity distribution near the intakes, but this effect diminished as the distance from the intake increased. Different intake shapes resulted in different iso-velocity contour shapes, and flow boundary effects influenced the velocity distribution.