波生流对海岸污染物输移的影响

The effects of wave-induced currents on the transport of pollutant outside and inside surf zone

通过物理模型实验对海岸波浪作用下污染物运动特性进行了分析,重点分析了质量输移流、沿岸流、沿岸流不稳定运动及破波带内旋涡运动等海岸水动力因素的影响.实验中坡度分别取为1∶100和1∶40,实验中采用CCD摄像机记录墨水的运动轨迹,同步测量流体质点速度以及波面升高.实验表明,在破碎带外污染物主要受波浪非线性引起的质量输移流的影响;在破碎带内主要受沿岸流的影响,同时还受沿岸流不稳定运动及大尺度旋涡运动的影响.

The effects of longshore currents, Stokes mass transport by waves, large scale eddies and the instability of longshore currents on the transport of pollutant in a surf zone are discussed based on the experimental results. The physical experiments were conducted on the two plane beaches with the slope 1 ： 100 and 1 ： 40. The movements of pollutant （ink for the experiment ） being injected into the water through point sources are recorded by a CCD camera, the fluid particle velocities and wave surface elevations were measured simultaneously. The experiment shows that the transport of pollutant is driven by Stokes mass transport outside the surf zone and by the longshore currents inside the surf zone, it also is affected strongly by the large-scale eddies and the instability of longshore currents.