Trapezoidal clapboard array: Innovative approach to vortex suppression in the lateral forebay

In light of the forebay of a lateral pump station in Shaanxi Province, numerical simulation and engineering tests were employed to analyze the correlation between the formation of multiple vortices and sediment deposition in the lateral forebay. Building upon this foundation, a total of 24 distinct rectification measures were proposed to scrutinize the alteration in flow regime within the lateral forebay, followed by an engineering test to validate the optimal scheme in the absence of rectification measures. The findings from the engineering test of the lateral forebay were consistent with the outcomes of the numerical simulation. This marked the inaugural proposition of a trapezoidal array clapboard within a lateral forebay. By adjusting the position, rotating the clapboard angle, and selecting the optimal scheme 24, the flow velocity uniformity at section C1-2 reached 93.16%, the deflection angle measured 94.32°, and the vortex area reduction rate was 87.73%, significantly mitigating the vortex impact on this section. Within section C1-3, the flow velocity uniformity attained 96.58%, the deflection angle measured 86.43°, and the vortex area reduction rate in this section amounted to 81.26%. Through the analysis of these two sections, the scheme's accuracy was validated. Additionally, the sediment deposition thickness decreased by 2.39 m under scheme 24, thus ensuring favorable operational conditions for the inlet forebay of the lateral pump station.