光滑壁面明渠底壁切应力试验研究

在分析Preston管量测试验资料的基础上,对比了明渠均匀流和非均匀流的底壁切应力在不同水力条件下的规律,指出断面中心处底壁切应力、平均底壁切应力和切应力的分布等几个切应力公式在均匀流时适用,在非均匀流时不全适用.均匀流时,切应力在同一坡度下随流量的增加而增大,在同一流量下随坡度的增加而增大;非均匀流时,在相对水深相同时,其相对底壁切应力大致相同.

Experimental study on bed shear stress in smooth open channels

Based on experimental data measured with a Preston tube,bed shear stresses in uniform and non-uniform flows in open channels were compared under different hydraulic conditions.It is concluded that the formulas for bed shear stress along the center-line,the mean bed shear stress and the bed shear stress distribution are applicable in uniform flow,but not all of the formulas are applicable in non-uniform flow.For uniform flow,the shear stress increases with the discharge at the same slope,and it increases with the slope at the same discharge,while the bed shear stresses in non-uniform flow are almost the same at the same relative water depth.