大管径排水管渠机械搅拌清淤参数试验研究

Experimental research for parameters of mechanical dredging system for draining pipe-canal with large diameter

为给大管径排水管渠清淤系统设计提供相应的参数,采用有机玻璃制作排水管渠模型,以沙粒模拟代表性淤积物,利用2D-PIV系统对螺旋桨搅拌的机械清淤参数进行了试验研究。对不同粒径沙粒在螺旋桨搅拌作用下起动和完全悬浮两种状态时的流场情况进行了考察,探讨了机械搅拌作用下的水流状态对沙粒的作用效果和规律。试验证实机械搅拌的清淤技术思路可行,起动和悬浮沙粒的粒径可由螺旋桨转速来控制,同时,加大螺旋桨转速可有效增强搅拌冲刷的强度和效果。

To provide the correlative parameter for the design of mechanical dredging system of large draining pipe- canal,a plexiglass draining model test using the propeller mixer was conducted,in which the sand particle was adopted as representative deposit,and 2D- PIV system was used as the measuring device. Through the test,the flow- field in two cases was studied,namely the incipient motion and suspension of different size particles that were stirred by propeller. The effect and law of interaction between flow state and sand particle under mechanical stir is discussed. The model test verifies the applicability of dredging by mechanical mixing,in which the size of incipient and suspension particles could be controlled by rotating speed of propeller,so it is applicable to strengthen the dredging effect by boosting the propeller speed.