【摘要】 为研究矩形多桥墩绕流水力特性，利用粒子图像测速(particle image velocimetry, PIV)技术，对不同纵、横间距比T/L、B/D方形布置四矩形桥墩和并列两矩形桥墩开展绕流试验，分析其流场分布、紊动强度、雷诺应力等水力特性。结果表明：1.5≤T/L=B/D≤2.5时，存在分界线X=200 mm使得时均流速从四矩形桥墩布置高于两并列矩形桥墩，变为后者高于前者。紊动强度在并列两矩形桥墩布置时，断面大致呈M形分布，而在四矩形桥墩时对称性则不明显，且其紊动强度总体低于两矩形桥墩。当T/L=B/D=1.0时，四矩形桥墩两侧雷诺应力整体呈现正负交替的反对称四极子分布，随着间距比的增大，下游桥墩两侧极子中心点位置向上游偏移。研究结果揭示了矩形桥墩不同间距比条件下的绕流特性，对类似水利工程中桥墩布置具有一定参考价值。更多还原

【Abstract】 To investigate the hydrodynamic characteristics around rectangular multi-piers, PIV(particle image velocimetry) technology was utilized to conduct flow experiments on configurations with different longitudinal and transverse spacing ratios(T/L,B/D) including arrangements of four rectangular piers and two parallel rectangular piers. The flow field distribution, turbulence intensity, and reynolds stress were analyzed. The results show that when 1.5≤T/L=B/D≤2.5, a boundary at X=200 mm causes the time-averaged velocity to be higher for the arrangement of four rectangular piers compared to the two parallel rectangular piers, with the latter arrangement exhibiting higher velocities downstream. The turbulence intensity for the two parallel rectangular piers exhibits a generally M-shaped distribution across the section, whereas in the arrangement of four rectangular piers, the symmetry is less apparent, and the turbulence intensity is overall lower than in the two-pier configuration. When T/L=B/D=1.0, the Reynolds stress on both sides of the four rectangular piers follows an alternating antisymmetric quadrupole distribution. As the spacing ratio increases, the center points of the downstream pier’s quadrupoles shift upstream. The findings reveal the flow characteristics of rectangular piers under varying spacing ratios, providing valuable insights for pier arrangement in similar hydraulic engineering projects.更多还原