Hot-Film Response in Three-Dimensional Highly Turbulent Flows
A methodology is described for accurate turbulence measurements with hot film or hot wires even at turbulent intensities as high as 100%. The assumptions involved and the approximations...
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)....
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....
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...
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...
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...
Comparison of Current Meters Used for Stream Gaging
The U.S. Geological Survey (USGS) is field and laboratory testing the performance of several current meters used throughout the world for stream gaging. Meters tested include horizontal-axis...
LDV System for Towing Tank Applications
The design, construction, testing, and operation of a two-dimensional LDV system for use in a towing tank is described. The primary design considerations were underwater application, minimal...
Experimental Study on Unsteady Flow in Open Channels with Flood Plains
Hydraulic characteristics of unsteady flows were investigated experimentally in open channels with flood plains using a computer-controlled water supply system. Some noticeable features...
Coherent Structures in Compound Open-Channel Flows by Making Use of Particle-Tracking Visualization Technique
In this study, images of very small 100 ?m diameter particles uniformly suspended in compound open-channel flows were recorded on an optic disc using a high-sensitive CCD camera and 2W...
Return to search