Study of Effective Parameters on Performance of Vortex Settling Basins Using Taguchi Method

In this study, the performance of a vortex settling basin (VSB) with a clockwise circulation was experimentally evaluated. The inlet flow rate was in the range of $8–22\mathrm{L}/\mathrm{s}$. Based on the Taguchi and response surface methods, the effects of inlet flow ($Q_{\mathrm{in}}$), central orifice diameter ($d_o$), sediment particle diameter ($d_s$), end sill height ($S_{\mathrm{out}}$), and outlet weir height ($W$) were investigated. The orthogonal array, signal-to-noise ratio (SNR), and ANOVA were used to study the performance of the VSB. The inlet canal efficiency, trapping efficiency, water abstraction ratio, and total performance were measured and the SNR calculated. The total performance of the VSB was calculated based on the inlet canal efficiency, trapping efficiency, and water abstraction ratio. The factors $Q_{\mathrm{in}}$, $W$, $S_{\mathrm{out}}$, $d_o$, and $d_s$ were ranked first to fifth with respect to impact on total performance. Based on dimensional analysis and experimental data analysis, total performance receives direct influence from $Q_{\mathrm{out}}/Q_{\mathrm{in}}$ while being inversely affected by $S_{\mathrm{out}}/H_{\mathrm{in}}$, $W/H_{\mathrm{in}}$, and $d_o/H_{\mathrm{in}}$. The highest total performance was obtained for $S_{\mathrm{out}}/H_{\mathrm{in}}=0.265$, $W/H_{\mathrm{in}}=0.159$, $Q_{\mathrm{out}}/Q_{\mathrm{in}}=0.915$, $D_{50}/H_{\mathrm{in}}=0.0019$, and $d_o/H_{\mathrm{in}}=0.370$.