Experimental Study on Turbulent Structures in Unsteady Open-channel Flows
Turbulence measurements in unsteady open-channel flows over smooth beds were conducted accurately by the simultaneous use of two-component LDA system and water-wave gauges. In the inner...
Response of Velocity and Turbulence to Abrupt Changes from Smooth to Rough Beds in Open-channel Flows
Response of velocity distribution and turbulence characteristics to abrupt changes of bed roughness have been investigated experimentally with two-component laser Doppler anemometer (LDA)....
Development of a Visual Method to Track the Movement of Hydrogen Bubbles in a Laboratory Flume
The current study proposes a visual method for tracking the hydrogen bubbles position with time in a 2-D space. The experiment is filmed from above with a video camera. The obtained movie...
High-speed Video Analysis of Sediment-Turbulence Interaction
Results from the analysis of high-speed video recordings of particle motion and simultaneous flow visualizations in the near wall region of a turbulent open channel flow are presented....
Optical Methods for Sediment-Laden Flows
A method of distinguishing between the signals from the liquid-seed particles and sediment particles, while using LDV in sediment-laden flows, is described. The validity of the method...
Visual Investigation of Field Bed-Load Sampling
An instrument for bed load sampling was developed consisting of an underwater video camera for visual observations. This instrument is called the Delft-Nile sampler and its design, efficiency...
Estimation of Mean Velocity for Flow Under Ice Cover
Methods of estimating mean velocity in a vertical from point velocity measurements are compared for an ice-covered channel. The comparison is based on velocity profiles obtained from a...
Effects of Simulated Ice on the Performance of Price Type-AA Current Meter Rotors
Slush ice readily adheres to the standard metal rotor of the winter Price type-AA current meter and affects the ability of the meter to measure the flow velocity accurately. Tests conducted...
Innovative Instrumentation for a Physical Model of River Ice Transport
Large physical models often require the use of innovative instrumentation and measurement techniques. Hydraulic models that attempt to simulate the effects of stationary ice covers put...
Developing Air Concentration and Velocity Probes for Measuring Highly-Aerated, High-Velocity Flow
The U.S. Bureau of Reclamation's stepped spillway overtopping protection research program required velocity and air concentration profile data be obtained during testing in a large, 15.2-m-high...
Void Fraction Measurement Techniques for Gas-Liquid Bubbly Flows in Closed Conduits; A Literature Review
This paper provides a review of void fraction measuring techniques for gas-liquid bubbly flows in closed conduits with emphasis on the suitability of these methods for air-water bubbly...
Measuring Air Concentration in Flowing Air-Water Mixtures
This paper describes the use of an electrical conductivity probe to determine aeration of a plunge pool by an overfall nappe. The probe was calibrated using an apparatus designed to provide...
Application of a Needle Probe in Measuring Local Parameters in Air-Water Flow
In this paper, development of a double needle probe for measuring local parameters in air-water mixtures is explained. This probe is designed to measure flow velocities up to 10 m/s and...
A New Basic Principle for a New Series of Hydraulic Measurements. Erosion by Abrasion, Corrosion, Cavitation and Sediment Concentration
The DECAVER is a novel apparatus able to make new measurements in various domains where an erosion is produced in an aqueous medium. It gives the erosion rate and the accumulated erosion....
Anomalous Measurements in a Compound Duct
An anomalous velocity distribution on the 'flood plain' of a compound duct is reported and discussed. The tentative conclusion is that the phenomenon is to be explained by the co-existence...
Hydrodynamic Forces in Hydraulic Jump Stilling Basins
The knowledge of hydrodynamic forces acting on hydraulic jump stilling basin slabs has been a research topic for the past four decades. Published methodologies for computing the hydrodynamic...
Measurements of the Hydrodynamic Lift and Drag Forces Acting on Riprap Side Slope
Direct measurements have been made of lift and drag forces acting on a 20.1 mm spherical particle placed within the riprapped 1.5 H: 1 V side slope of a 10 m long channel which was protected...
Recent Applications of Acoustic Doppler Current Profilers
A Broadband acoustic Doppler current profiler (BB-ADCP) is a new instrument being used by the U.S. Geological Survey (USGS) to measure stream discharge and velocities, and bathymetry....
Acoustic-Doppler Velocimeter (ADV) for Laboratory Use
A remote-sensing, three-dimensional (3D) velocity sensor has been developed and tested for use in physical model facilities. The sensor is based on the Acoustic Doppler principle and measures...
Field Performance of an Acoustic Scour-Depth Monitoring System
The Herbert C. Bonner Bridge over Oregon Inlet serves as the only land link between Bodie and Hatteras Islands, part of the Outer Banks of North Carolina. Periodic soundings over the past...
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