Doctoral Dissertation Research in Geography and Regional Science

基本的水力变量，如排水量和水流剪切应力，是从速度剖面中推导出来的，假设它们的形状是对数的。最近的研究表明，粗层状河流的速度分布往往不是对数的，而是分段的或s形的。本博士论文的研究重点是影响粗质天然河流流速剖面形态和空间变化的各种因素。在这个项目中，将收集两组速度剖面数据：一组来自纽约和魁北克的10条天然粗层溪流的测量数据，另一组来自布法罗纽约州立大学水力学实验室的一个带有粗层物质的水槽。这两组测量将分别阐明不同的河床粗糙度对速度剖面的形状和空间变化的影响，并检查在现场难以分离的诸如河道坡度等变量的影响。这两组互补的野外和实验室数据将使更准确地估计水流量、床沙夹带和床沙输运率成为可能。这项研究将有助于更好地理解具有大粗糙度元素的通道中的流动和阻力。地表水资源开发中遇到的许多地貌学、工程学和环境科学问题的解决取决于开发更精确的洪水路径模型和输沙模型。该项目还将为有前途的年轻学者提供继续发展独立研究技能的绝佳机会。

Basic hydraulic variables, such as water discharge and flow shear stress, are derived from velocity profiles assuming that their shape is logarithmic. Recent studies have demonstrated that velocity profiles in coarse bedded streams are often not logarithmic but segmented or S-shaped. This doctoral dissertation research will focus on the various factors affecting the shape and spatial variation of velocity profiles in natural streams with coarse bed material. In this project two sets of data will be collected on velocity profiles: one set of measurements from 10 natural coarse bedded streams in New York and Quebec and the other set from a flume with a bed of coarse material in the Hydraulics Laboratory at the State University of New York at Buffalo. Respectively, these two sets of measurements will permit the elucidation of the effect of varying bed roughness on the shape and spatial variation of velocity profiles and the examination of the effect of variables such as channel slope that are difficult to isolate in the field. These two complementary sets of field and laboratory data will make possible the more accurate estimation of water discharge, bed sediment entrainment, and bed sediment transport rates. This research will contribute to a better understanding of flow and resistance in channels with large roughness elements. The solutions to many problems in geomorphology, engineering, and environmental science encountered in the exploitation of surface water resources depend upon developing more accurate flood routing models and sediment transport models. The project also will provide an excellent opportunity for a promising young scholar to continue to develop independent research skills.