摘要
试验表明高含沙水流或高浓度浆液具有明显的宾汉体特性、宾汉极限剪切力是高含沙水流的重要物理特性.但这种剪切力在流动条件下是否继续保留,及其对流动特性的影响至今尚无统一认识.本文在评述已有试验结果基础上,提出一种新的试验方法,测定了宾汉极限剪切力在流动浆液中的变化规律.为高含沙水流,浆体管道的阻力及泥沙运动有关计算提供了依据.
It is known that the hyperconcentrated flow can be described as Bin-gham fluid.The value of yield stress, caused by the floculation of fine particles in the water characterized variables, depending on the intensity of flow. In this paper, a new relationship of structure coefficient A, which is defined as the ratio of yield stress in flowing condition τBT to that of Theological parameter τB, and effective Reynold number Re* was developed by results of experiments. It was found that the value of K becomes about 0.5 as Re* equal to 3000. This means that the yield stress of hyperconcentrated flow remains about 50% in comparison with the value obtained by rheological experiment at the flow regime in laminar-turbulent flow; λ approaches to zero as Re* = 3 - 4×144. It means that the yield stress will not exist in turbulent flow of high intensity.
出处
《泥沙研究》
CSCD
北大核心
1991年第4期13-23,共11页
Journal of Sediment Research
基金
国家自然科学基金
