[1] We have conducted surveys of gullies that developed in a small, steep watershed in the Idaho Batholith after a severe wildfire followed by intense precipitation. We measured gully length and cross sections to estimate the volumes of sediment loss due to gully formation. These volume estimates are assumed to provide an estimate of sediment transport capacity at each survey cross section from...

Field studies of forest gravel-bed rivers in northwestern Washington and southeastern Alaska demonstrate that bed-surface grain size is responsive to hydraulic roughness caused by bank irregularities, bars, and wood debris. We evaluate textural response by comparing reach-average median grain size (D50) to that predicted from the total bank-full boundary shear stress (t0bf), representing a hypo...

[1] This paper examines near-bottom shear stresses at two locations in a small, highly stratified estuary: the Navesink River, New Jersey, USA. The shear stresses obtained from acoustic Doppler current profilers (ADCPs) operating in the recently developed mode 11 at a high spatial resolution are examined in detail. Measurement noise of the ADCP is estimated using autocorrelation analyses and is...

We present an experimental and computational investigation of time-varying flow in an idealized fully occluded 45 degrees distal end-to-side anastomosis. Two geometric configurations are assessed, one where the centerlines of host and bypass vessels lie within a plane, and one where the bypass vessel is deformed out of the plane of symmetry, respectively, termed planar and non-planar. Flow expe...

Bed shear stress is an important measure of benthic habitats since it related to many ecological processes. In this study, we focused on the fluctuating characteristics in rough-bed open-channel flows. The roughness element method was adopted mimic natural rough beds and Improved Delayed Detached Eddy Simulation (IDDES) model used obtain comprehensive information about near bed. Three arrangeme...

The effects of channel bed disturbance on benthic chlorophyll a accrual were examined in three reaches of the Williams Fork River, CO, USA. A field calibrated multidimensional hydraulic model was used for estimation of shear-stress distributions. Sediment grain size was used to determine the critical shear stress for bed movement. Disturbance at a given location is defined as the percentage of ...

Replicate velocity observations using conventional equipment under typical field conditions are used to evaluate the precision of different methods for estimating local boundary shear stress from velocity measurements. The bed shear velocity u, can be estimated within 3% using the depth-averaged velocity in the vertically averaged logarithmic velocity profile. To be accurate, this method is lim...

the research was conducted in order to determine the bending stress, young’s modulus, shearing stress, and shearing energy of safflower stalk as a function of moisture content and stalk region. the bending forces were measured at different moisture contents and the bending stress and the young’s modulus were calculated from these data. for measuring the shear forces, the stalk specimens were se...

The numerical modeling of a 2D flow around a horizontal cylinder near a rigid bed with the gap ratios G/D = 0, 0.2, 0.3 at Reynolds numbers 840, 4500, 9000, and 9500 is investigated by using weakly compressible smoothed particle hydrodynamics. The velocity field and the separation angles from the present simulations are compared with those obtained from the experimental measurements and are in ...

Acoustic Doppler velocity profiler (ADVP) measurements of instantaneous threedimensional velocity profiles over the entire turbulent boundary layer height, δ, of rough-bed open-channel flows at moderate Reynolds numbers show the presence of large scale coherent shear stress structures (called LC3S herein) in the zones of uniformly retarded streamwise momentum. LC3S events over streamwise distan...