Manning's roughness coefficient for flow over bare soil is needed in order to determine other hydraulic parameters such as flow depth and velocity in overland flow, parameters needed to calculate streampower and shear stress in erosion process studies. A modified equation of Manning's n was developed to estimate flow velocity in shallow overland flow in experiments undertaken in a 5.8 by 1 m fl...

A kind of 2.5-dimensional C/C-SiC composites was fabricated by using Isothermal Chemical Vapour Infiltration process (ICVI). Frictional properties of this material were evaluated by using MM-1000 under dry condition. Average dynamic friction coefficient of it was 0.16, static friction coefficient and average coefficient stability were 0.15 and 0.56, respectively. However, weight wear rate was l...

With nanotextured surfaces and interfaces increasingly being encountered in technological and biomedical applications, there is a need for a better understanding of frictional properties involving such surfaces. Here we report friction measurements of several nanostructured surfaces using an Atomic Force Microscope (AFM). These nanostructured surfaces provide well defined model systems on which...

Liquid wetting of a surface is omnipresent in nature and the advance of micro-fabrication and assembly techniques in recent years offers increasing ability to control this phenomenon. Here, we identify how surface roughness influences the initial dynamic spreading of a partially wetting droplet by studying the spreading on a solid substrate patterned with microstructures just a few micrometers ...

in this paper twelve different empirical resistance coefficients expressed in terms of manning's roughness are used apiece in seventeen known compositing methods. the data obtained from ten different cross-sections of the sefidrood river, iran, are used for the evaluation of the empiricalformulas. the present case-study is selected from a reach with gravel bed topology. then no remarkable bed f...

abstract for investigating the effect of bed form in alluvial channels on the amount of bed load transport, a set of experiments was carried out in a tilting flume under unsteady flow conditions (hydrograph). the produced hydrographs were in triangular form with a maximum discharge of 30 to 45 lit/s/m. three size of sediment particles were used with equal to 1.5, 2.1 and 3.0mm, clear water with...

Representation of the marine environment is key for reliable coastal hydrodynamic models. This study investigates implications common depth-averaged model configuration choices in sufficiently characterising seabed geometry and roughness. In particular, applications requiring a high level accuracy and/or exhibiting complex flow conditions may call greater detail representation than typically ad...

The discrete linear cascade model DLCM was applied for historical flow routing along the Nebraska City–Rulo section of the Missouri River in southeastern Nebraska. With the help of optimized model parameters it has been possible to identify the triggering mechanism responsible for historical changes in the stage-discharge relationship at Rulo over the 1952–2006 period, following construction of...

Flow velocity measurements using point-velocity meters are normally obtained by sampling one, two or three velocity points per vertical profile. During high floods their use is inhibited due to the difficulty of sampling in lower portions of the flow area. Nevertheless, the application of standard methods allows estimation of a parameter, α, which depends on the energy slope and the Manning rou...