Comparison of Bed Shear under Non-Breaking and Breaking Solitary Waves
Comparison of Bed Shear under Non-Breaking and Breaking Solitary Waves
复制标题
非破碎和破碎孤立波下的底剪比较
DOI：
10.1260/1759-3131.2.4.259
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
T. Baldock
中科院分区：
文献类型：
--
作者：
Jaya Kumar Seelam;T. Baldock
提出了代表海啸的孤立波和孤立孔下床面剪切的新的实验测量结果。用剪切仪直接测量了床面总剪应力。用超声波测速仪测量了孤立波特性，用声学多普勒测速仪测量了自由流速度。测量是在层流和过渡流区(∼104Re<；∼105)进行的。这类数据在文献中很少见到。在没有直接测量的情况下，剪应力是使用速度剖面间接估计的，或使用标准摩擦系数来推断的。然而，这种间接方法有其局限性，例如在非定常水动力条件和相对较大的粗糙度下，这两种方法的假设都不再有效。在波高水深比为0.12~0.69的光滑平坦河床上，进行了168次包括孤立波和钻孔的试验。采用傅立叶积分法和卷积积分法进行了剪应力预测的解析建模。本文给出了实测和预测的床面剪切力或摩擦应力的比较，以及对传统波浪摩阻系数的估计。总体而言，模型能够较好地预测床面剪应力，预测精度令人满意。
New experimental measurements of bed shear under solitary waves and solitary bores that represent tsunamis are presented. The total bed shear stress was measured directly using a shear cell apparatus. The solitary wave characteristics were measured using ultrasonic wave gauges and free stream velocities were measured using an Acoustic Doppler Velocimeter. The measurements were carried out in laminar and transitional flow regimes (∼104 < Re < ∼105). This sort of data is sparsely available in literature. In the absence of direct measurements, shear stress is indirectly estimated using velocity profiles or is inferred using standard friction factors. However, this indirect method has its limitations, e.g., under unsteady hydrodynamic conditions and relatively large roughness the assumptions of both approaches are no longer valid. More than 168 experimental runs comprising solitary waves and bores were carried out over a smooth flat bed with wave height to water depth ratio varying between 0.12 and 0.69. Analytical modeling was carried out to predict shear stresses using Fourier and convolution integration methods. This paper presents comparison of the measured and predicted bed shear stress or skin friction stress, together with estimates of traditional wave friction factors. Overall, the models can predict the bed shear stress with a satisfactory degree of accuracy.
影响因子：
4.4
作者：
Barnes, M. P.;O'Donoghue, T.;Baldock, T. E.
通讯作者：
Baldock, T. E.