Kevin A Oberg (Former Employee)
Science and Products
Filter Total Items: 65
Density currents in the Chicago River: Characterization, effects on water quality, and potential sources
Bidirectional flows in a river system can occur under stratified flow conditions and in addition to creating significant errors in discharge estimates, the upstream propagating currents are capable of transporting contaminants and affecting water quality. Detailed field observations of bidirectional flows were made in the Chicago River in Chicago, Illinois in the winter of 2005-06. Using multiple
Authors
P. Ryan Jackson, Carlos M. Garcia, Kevin A. Oberg, Kevin K. Johnson, Marcelo H. Garcia
Measuring gravity currents in the Chicago River, Chicago, Illinois
Recent studies of the Chicago River have determined that gravity currents are responsible for persistent bidirectional flows that have been observed in the river. A gravity current is the flow of one fluid within another caused by a density difference between the fluids. These studies demonstrated how acoustic Doppler current profilers (ADCP) can be used to detect and characterize gravity currents
Authors
K. A. Oberg, J. A. Czuba, K. K. Johnson
Errors in acoustic doppler profiler velocity measurements caused by flow disturbance
Acoustic Doppler current profilers (ADCPs) are commonly used to measure streamflow and water velocities in rivers and streams. This paper presents laboratory, field, and numerical model evidence of errors in ADCP measurements caused by flow disturbance. A state-of-the-art three-dimensional computational fluid dynamic model is validated with and used to complement field and laboratory observations
Authors
D. S. Mueller, J.D. Abad, C.M. Garcia, J. W. Gartner, M.H. Garcia, K. A. Oberg
Characterizing a December 2005 density current event in the Chicago River, Chicago, Illinois
During the winter months, the Chicago River in Chicago, Illinois is subject to bi-directional flows, and density currents are thought to be responsible for these flow variations. This paper presents detailed field measurements using three acoustic Doppler current profiler instruments and simultaneous water-quality measurements made during December 2005. Observations indicate that the formation of
Authors
C.M. Garcia, P.R. Jackson, K. A. Oberg, K. K. Johnson, M.H. Garcia
Validation of streamflow measurements made with acoustic doppler current profilers
The U.S. Geological Survey and other international agencies have collaborated to conduct laboratory and field validations of acoustic Doppler current profiler (ADCP) measurements of streamflow. Laboratory validations made in a large towing basin show that the mean differences between tow cart velocity and ADCP bottom-track and water-track velocities were -0.51 and -1.10%, respectively. Field valid
Authors
K. Oberg, D. S. Mueller
ADCP measurements of gravity currents in the Chicago River, Illinois
A unique set of observations of stratified flow phenomena in the Chicago River was made using an upward-looking acoustic Doppler current profiler (ADCP) during the period November 20, 2003 to February 1, 2004. Water density differences between the Chicago River and its North Branch (NB) seem to be responsible for the development of gravity currents. With the objective of characterizing the occurre
Authors
C.M. Garcia, K. Oberg, M.H. Garcia
Evaluation of mean velocity and turbulence measurements with ADCPs
To test the ability of acoustic Doppler current profilers (ADCPs) to measure turbulence, profiles measured with two pulse-to-pulse coherent ADCPs in a laboratory flume were compared to profiles measured with an acoustic Doppler velocimeter, and time series measured in the acoustic beam of the ADCPs were examined. A four-beam ADCP was used at a downstream station, while a three-beam ADCP was used a
Authors
E.A. Nystrom, C.R. Rehmann, K. A. Oberg
Quality-assurance plan for discharge measurements using acoustic Doppler current profilers
No abstract available.
Authors
Kevin A. Oberg, Scott E. Morlock, William Scott Caldwell
Effect of temporal resolution on the accuracy of ADCP measurements
The application of acoustic Doppler current profilers (ADCP's) in river flow measurements is promoting a great deal of progress in hydrometry. ADCP's not only require shorter times to collect data than traditional current meters, but also allow streamflow measurements at sites where the use of conventional meters is either very expensive, unsafe, or simply not possible. Moreover, ADCP's seem to of
Authors
J. A. Gonzalez-Castro, K. Oberg, James J. Duncker
Measurement of Turbulence with Acoustic Doppler Current Profilers - Sources of Error and Laboratory Results
Acoustic Doppler current profilers (ADCPs) provide a promising method for measuring surface-water turbulence because they can provide data from a large spatial range in a relatively short time with relative ease. Some potential sources of errors in turbulence measurements made with ADCPs include inaccuracy of Doppler-shift measurements, poor temporal and spatial measurement resolution, and inaccur
Authors
E.A. Nystrom, K. A. Oberg, C.R. Rehmann
Hydrodynamic field study of a shallow estuarine subembayment, Sherman Lake, California
Sherman Lake, California, has two hydrodynamically distinct regions: a tidally forced jet located along the eastern flank that creates an important hydraulic connection between the Sacramento and San Joaquin Rivers, and a relatively quiescent area in the west. The forcing mechanisms driving circulation and transport are spatially variable in Sherman Lake, a characteristic, we are finding, that is
Authors
C.A. Ruhl, J.R. Burau, R.N. Oltmann
Use of Acoustic Doppler Instruments for Measuring Discharge in Streams with Appreciable Sediment Transport
The use of Acoustic Doppler current profilers (ADCP) for measuring discharge in streams with sediment transport was discussed. The studies show that the acoustic frequency of an ADCP in combination with the sediment transport characteristics in a river causes the ADCP bottom-tracking algorithms to detect a moving bottom. A moving bottom causes bottom-tracking-referenced water velocities and discha
Authors
D. S. Mueller
Science and Products
- Publications
Filter Total Items: 65
Density currents in the Chicago River: Characterization, effects on water quality, and potential sources
Bidirectional flows in a river system can occur under stratified flow conditions and in addition to creating significant errors in discharge estimates, the upstream propagating currents are capable of transporting contaminants and affecting water quality. Detailed field observations of bidirectional flows were made in the Chicago River in Chicago, Illinois in the winter of 2005-06. Using multipleAuthorsP. Ryan Jackson, Carlos M. Garcia, Kevin A. Oberg, Kevin K. Johnson, Marcelo H. GarciaMeasuring gravity currents in the Chicago River, Chicago, Illinois
Recent studies of the Chicago River have determined that gravity currents are responsible for persistent bidirectional flows that have been observed in the river. A gravity current is the flow of one fluid within another caused by a density difference between the fluids. These studies demonstrated how acoustic Doppler current profilers (ADCP) can be used to detect and characterize gravity currentsAuthorsK. A. Oberg, J. A. Czuba, K. K. JohnsonErrors in acoustic doppler profiler velocity measurements caused by flow disturbance
Acoustic Doppler current profilers (ADCPs) are commonly used to measure streamflow and water velocities in rivers and streams. This paper presents laboratory, field, and numerical model evidence of errors in ADCP measurements caused by flow disturbance. A state-of-the-art three-dimensional computational fluid dynamic model is validated with and used to complement field and laboratory observationsAuthorsD. S. Mueller, J.D. Abad, C.M. Garcia, J. W. Gartner, M.H. Garcia, K. A. ObergCharacterizing a December 2005 density current event in the Chicago River, Chicago, Illinois
During the winter months, the Chicago River in Chicago, Illinois is subject to bi-directional flows, and density currents are thought to be responsible for these flow variations. This paper presents detailed field measurements using three acoustic Doppler current profiler instruments and simultaneous water-quality measurements made during December 2005. Observations indicate that the formation ofAuthorsC.M. Garcia, P.R. Jackson, K. A. Oberg, K. K. Johnson, M.H. GarciaValidation of streamflow measurements made with acoustic doppler current profilers
The U.S. Geological Survey and other international agencies have collaborated to conduct laboratory and field validations of acoustic Doppler current profiler (ADCP) measurements of streamflow. Laboratory validations made in a large towing basin show that the mean differences between tow cart velocity and ADCP bottom-track and water-track velocities were -0.51 and -1.10%, respectively. Field validAuthorsK. Oberg, D. S. MuellerADCP measurements of gravity currents in the Chicago River, Illinois
A unique set of observations of stratified flow phenomena in the Chicago River was made using an upward-looking acoustic Doppler current profiler (ADCP) during the period November 20, 2003 to February 1, 2004. Water density differences between the Chicago River and its North Branch (NB) seem to be responsible for the development of gravity currents. With the objective of characterizing the occurreAuthorsC.M. Garcia, K. Oberg, M.H. GarciaEvaluation of mean velocity and turbulence measurements with ADCPs
To test the ability of acoustic Doppler current profilers (ADCPs) to measure turbulence, profiles measured with two pulse-to-pulse coherent ADCPs in a laboratory flume were compared to profiles measured with an acoustic Doppler velocimeter, and time series measured in the acoustic beam of the ADCPs were examined. A four-beam ADCP was used at a downstream station, while a three-beam ADCP was used aAuthorsE.A. Nystrom, C.R. Rehmann, K. A. ObergQuality-assurance plan for discharge measurements using acoustic Doppler current profilers
No abstract available.AuthorsKevin A. Oberg, Scott E. Morlock, William Scott CaldwellEffect of temporal resolution on the accuracy of ADCP measurements
The application of acoustic Doppler current profilers (ADCP's) in river flow measurements is promoting a great deal of progress in hydrometry. ADCP's not only require shorter times to collect data than traditional current meters, but also allow streamflow measurements at sites where the use of conventional meters is either very expensive, unsafe, or simply not possible. Moreover, ADCP's seem to ofAuthorsJ. A. Gonzalez-Castro, K. Oberg, James J. DunckerMeasurement of Turbulence with Acoustic Doppler Current Profilers - Sources of Error and Laboratory Results
Acoustic Doppler current profilers (ADCPs) provide a promising method for measuring surface-water turbulence because they can provide data from a large spatial range in a relatively short time with relative ease. Some potential sources of errors in turbulence measurements made with ADCPs include inaccuracy of Doppler-shift measurements, poor temporal and spatial measurement resolution, and inaccurAuthorsE.A. Nystrom, K. A. Oberg, C.R. RehmannHydrodynamic field study of a shallow estuarine subembayment, Sherman Lake, California
Sherman Lake, California, has two hydrodynamically distinct regions: a tidally forced jet located along the eastern flank that creates an important hydraulic connection between the Sacramento and San Joaquin Rivers, and a relatively quiescent area in the west. The forcing mechanisms driving circulation and transport are spatially variable in Sherman Lake, a characteristic, we are finding, that isAuthorsC.A. Ruhl, J.R. Burau, R.N. OltmannUse of Acoustic Doppler Instruments for Measuring Discharge in Streams with Appreciable Sediment Transport
The use of Acoustic Doppler current profilers (ADCP) for measuring discharge in streams with sediment transport was discussed. The studies show that the acoustic frequency of an ADCP in combination with the sediment transport characteristics in a river causes the ADCP bottom-tracking algorithms to detect a moving bottom. A moving bottom causes bottom-tracking-referenced water velocities and dischaAuthorsD. S. Mueller - Data
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