合流制排水系统截流工程淤积分析与探测

Analysis and Inspection on Siltation of Intercepting Combined Sewer System

为研究承压截流井的淤积机理,应用CFD方法进行数值模拟,并以声纳现场实测数据检验.在基于DPM的临界床面切应力模型基础上,应用遗传算法的概率选择方法,提出颗粒'概率沉降'模型,可有效模拟淤积面形状和相对淤积厚度,这得到了声纳实测数据的验证.结果显示,截流井内x方向淤泥面呈斜坡状,存在位置不受流量影响的凸起;y方向淤泥面呈凹面状,中部存在凸起,两侧受冲刷而趋于平缓.声纳现场探测还发现,截流井内淤积厚度与旱流量有较强相关性;截流干管内淤积状况与相连的截流井有关.

In order to investigate the siltation mechanism of intercepting well with pressure, CFD was applied for numerical simulation, which was validated with field measurement data of sonar. On the basis of critical BSS model based on DPM, the probability selection method of GA was applied from a new point of view to put forward ＂probability sedimentation＂ model of particle. This model worked effectively on the simulation of silt surface and relatively siltation depth, which was validated with field measurement data of sonar. The results have shown that the silt surface of x-direction is a slope and there is a bulge with a loca- tion insensitive to flow. The silt surface of y-direction is concave and the middle surface swells while both sides tend to be flat because of scouring. The field measurement of sonar has shown that the silt depth in intercepting well is strongly relative to dry weather flow while the siltation condition of main intercepting pipe is relative to intercepting well.