Roughness Coefficient in Mountain Rivers
River discharge estimations require an evaluation of the river flow resistance that generally is related with Manning's roughness coefficient. The literature suggests different ways of...
Chezy Formula Versus Theory and Common Sense
Using the theoretical concepts of the uniform flow formula and the inverse solution of the Chezy equation it is shown that a channel shape may have considerable influence on the value...
Design of Manning's-Rougness-Coefficient Study in New York State
Field-collected hydraulic data can be used to compute roughness coefficients for channels with different hydraulic characteristics. Suggested criteria for the design of a roughness-coefficient...
An Analysis of Flow Velocity Profiles, Stream Bed Roughness, and Resistance to Flow in Natural Gravel Bed Streams
The characteristics of 82 flow velocity profiles were analyzed from nine different gravel bed stream reaches. A statistical test of the linearity of flow velocity profiles indicates that...
A new approach for the estimation of extreme roughness in torrents by Hydraulic and Photogrammetry
In this paper we present an approach to estimate extreme roughness in torrents based on the transformation of an irregular bed geometry of a torrent reach into a geometrically well determined...
Study of Friction Factors in the Upper Reaches of the Rio Grande
The purpose of this study is to investigate the determination of Manning's roughness in the upper Rio Grande river basin and compare results to other studies where Darcy Weisbach friction...
Evaluating Flow Resistance Using Height of Roughness Protrusions
On the basis of field measurements on the Sumava mountain rivers heights of roughness protrusions have been used for calculation of flow resistance. The result resistance equations, compared...
Flow Resistance of High-Gradient Gravel Channels
The flow resistance in terms of the friction factor for bank-full or high in-bank flows for 120 high-gradient gravel-bed rivers are examined. The friction factor f was divided into grain...
Roughness Coefficients for High-Gradient Channels in New York State
Manning's roughness coefficients (n values) were computed for a range of flows at six streams in New York State (USA) that have high energy gradients (greater than 0.002) and large median...
Bias in Regression Estimates of Manning's n
Selected equations for estimating roughness for gravel-bed streams were tested using a composite data set containing much of the data used to define the equations. All equations tested...
Bed Load Roughness in Supercritical Flow
A supercritical concrete channel has been proposed for Mission Creek located in Santa Barbara County, California. The proposed channel could transport gravels and cobbles as bed load during...
An Approach to the Calculation Method of Mean Sediment Size
Mean sediment size is an important parameter expressing the characteristics of sediment. Several calculation methods of mean sediment size which are popular at present almost have some...
Step Pool Geometry and Flow Characteristics in Low-Sediment-Storage Channel Beds
Data from two small ephemeral streams in Israel indicate that step pool geometry in bedrock channels is similar, in its salient features, to that in alluvial channels. For steep (>0.10)...
On Habitat Simulation in Mountain Rivers
Mountain rivers are quite different from other rivers and one of the characteristics that distinguish them from others is the large variation in velocities with time, with location in...
Sediment Transport in Sewers and Design Implications
Extended studies on sediment transport in sewers were conducted at the University of Newcastle upon Tyne and using this new as well as previously available data an attempt has been made...
Macro-Roughness Effects on Stream Reaeration
The gas transfer coefficient is key to modeling dissolved oxygen levels in streams. Engineers commonly predict it as a function of mean flow depth, velocity, and slope. Large errors are...
Determination of Sediment Profile for a Dry Flood Control Basin
A modification of the standard delta profile method was used to estimate the sediment profile in a dry flood control basin. Dry flood control basins do not have a normal operating pool...
Sheet Flow Resistance of Asphaltic Pavements
A statistical study has been conducted by the authors using 400 points of experimental data taken in the 1970's at Texas A&M for sheet flow runoff during artificial rainfall on...
Floating Cover Influence on Sediment Transport in Dune-Bed Channels
The results of laboratory flume experiments with a floating cover and a loose bed indicate that, relative to a free surface flow, the increased drag of a floating cover increases flow...
Theoretical study of unstable waves in the rapids of the river
This paper examines how the velocity distribution in free-surface flow affects the kinematic and dynamic velocities of disturbance waves on hillslopes or in high-gradient rivers, thereby...
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