淤泥絮体孔隙分形特性的提出、验证及应用

Proposal,proof and application of fractal characteristic of silt floc pores

由于淤泥中细颗粒泥沙的絮凝作用造成淤泥含水率较高且水分较难去除,淤泥絮体性质的研究逐渐成为淤泥处理研究中的重要内容.在前人研究的基础上,提出淤泥絮体孔隙具有分形特征的假设.以武汉沙湖淤泥为例,使用图像分析法检验这一假设的存在性,接着通过室内实验探讨了淤泥絮体孔隙分形维数的应用.实验结果表明:淤泥絮体孔隙具有统计意义上的分形特征,其二维分形维数越大,絮体孔隙总面积越大、等效孔径相差越大,淤泥沉降速度越小.

Because of the high rate of water content and the difficulty to remove the water resulted from the flocculation of fine sediment in silt,the researches on silt floc have been becoming the essential part of the study on the treatment of silt.Based on the previous researches,the paper puts forward the hypothesis that the silt floc pores take on fractal characteristic.Taking the silt in the Shahu Lake in Wuhan for example,the paper proves the hypothesis using image analysis;and then discusses the application of this hypothesis by laboratory experiment.It is concluded that the silt floc pores possess the fractal characteristic in statistical sense.The higher the 2-D fractal dimension is,the greater is the total area and aperture of floc pores and the lower is the silt settling velocity.