2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM)最新文献

{"title":"Direct force compensation on Lorentz force flowmeters for electrolyte flow measurements","authors":"S. Vasilyan, T. Frohlich","doi":"10.1109/CWTM.2015.7098115","DOIUrl":"https://doi.org/10.1109/CWTM.2015.7098115","url":null,"abstract":"A simplified method for contactless flow rate measurements of electrolytes in rectangular channel is proposed. Based on advancement in metering low conductive medias by Lorentz Force Velocimetry (LFV) an optimized model is described. System provides stable flow rate measurements in range of 0.4 to 2.5 m/s velocities for electrolytes down to 2 S/m conductivity. We demonstrate Lorentz force compensation measurement scheme for LFV applications by commonly known electromagnetic force compensation principle. Method realized through combination of relatively straightforward Magnetohydrodynamic (MHD), Electromagnetic, kinematic and electronic schemes. Its characteristics is discussed against recent developments in such a class of noncontact flowmenters. Results of measurements by experimental prototype at TU Ilmenau and generalized theoretical model of implemented scheme show potential use of this method for wide range of applications in liquid flow measurements. Practical interest includes metering electrolyte flows like tap water or glass melts with relative low conductivity of 10-4 to 10 S/m and high conductivities typical for liquid metals 106 S/m.","PeriodicalId":356185,"journal":{"name":"2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM)","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122990840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Velocity bias induced by flow patterns around ADCPs and associated deployment platforms","authors":"D. S. Mueller","doi":"10.1109/CWTM.2015.7098103","DOIUrl":"https://doi.org/10.1109/CWTM.2015.7098103","url":null,"abstract":"Velocity measurements near the Acoustic Doppler Current Profiler (ADCP) are important for mapping surface currents, measuring velocity and discharge in shallow streams, and providing accurate estimates of discharge in the top unmeasured portion of the water column. Improvements to ADCP performance permit measurement of velocities much closer (5 cm) to the transducer than has been possible in the past (25 cm). Velocity profiles collected by the U.S. Geological Survey (USGS) with a 1200 kHz Rio Grande Zedhead ADCP in 2002 showed a negative bias in measured velocities near the transducers. On the basis of these results, the USGS initiated a study combining field, laboratory, and numerical modeling data to assess the effect of flow patterns caused by flow around the ADCP and deployment platforms on velocities measured near the transducers. This ongoing study has shown that the negative bias observed in the field is due to the flow pattern around the ADCP. The flow pattern around an ADCP violates the basic assumption of flow homogeneity required for an accurate three-dimensional velocity solution. Results, to date (2014), have indicated velocity biases within the measurable profile, due to flow disturbance, for the TRDI 1200 kHz Rio Grande Zedhead and the SonTek RiverSurveyor M9 ADCPs. The flow speed past the ADCP, the mount and the deployment platform have also been shown to play an important role in the magnitude and extent of the velocity bias.","PeriodicalId":356185,"journal":{"name":"2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131138488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wave amplification and resonance in enclosed basins; a case study in haydarpasa port of Istanbul","authors":"R. Kian, A. Yalciner, Betul Aytore, A. Zaytsev","doi":"10.1109/CWTM.2015.7098153","DOIUrl":"https://doi.org/10.1109/CWTM.2015.7098153","url":null,"abstract":"The amplification of waves inside the ports becomes critical under extreme events (storms or tsunamis) by causing unexpected amplification and damage in the ports. The resiliency of harbors and coastal utilities against marine hazards is important for the post disaster recovery operations. Resonance oscillations and resultant wave amplifications inside the basins are other important adverse effects which cause damage on structures and interruption of harbor functions. Those are necessary for the post event recovery operations. One of the important utilities located in Istanbul coast near Marmara is the port of Haydarpasa where regular shaped basins were designed inside the harbor. The resonance oscillations, periods of free oscillations and flow pattern of long waves in Haydarpasa port under the actions of long waves are investigated using numerical model (NAMI DANCE). An initial impulse is inputted, and a simulation is performed. The time histories of water surface fluctuations are computed at several numerical gauge points inside the harbor. The spectral analysis by using Fast Fourier Transform technique is applied to the records of all numerical gauge points and respective spectrum curves are obtained. The peaks of spectrum curves of each numerical gauge location are also determined. The peaks of spectrum curves coincide with the resonance frequencies. The computed frequencies are discussed by comparing with the frequency of the waves which occur in the Marmara Sea in regard to their possible amplification and effects to Haydarpasa port.","PeriodicalId":356185,"journal":{"name":"2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126871508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quality assurance testing of acoustic doppler current profiler transform matrices","authors":"B. Armstrong, J. Fulford, K. Thibodeaux","doi":"10.1109/CWTM.2015.7098108","DOIUrl":"https://doi.org/10.1109/CWTM.2015.7098108","url":null,"abstract":"The U.S. Geological Survey (USGS) Hydrologic Instrumentation Facility (HIF) is nationally responsible for the design, testing, evaluation, repair, calibration, warehousing, and distribution of hydrologic instrumentation in use within the USGS Water Mission Area (WMA). The HIF's Hydraulic Laboratory has begun routine quality assurance (QA) testing and documenting the performance of every USGS WMA acoustic Doppler current profiler (ADCP) used for making velocity and discharge measurements. All existing ADCPs are being registered and tracked in a database maintained by the HIF, and called for QA checks in the HIF's Hydraulic Laboratory on a 3- year cycle. All new ADCPs purchased directly from the manufacturer as well as ADCPs sent to the HIF or the manufacturer for repair are being registered and tracked in the database and QA checked in the laboratory before being placed into service. Meters failing the QA check are sent directly to the manufacturer for repairs and rechecked by HIF or removed from service. Although this QA program is specific to the SonTek1 and Teledyne RD Instruments1, ADCPs most commonly used within the WMA, it is the intent of the USGS Office of Surface Water and the HIF to expand this program to include all bottom tracking ADCPs as they become available and more widely used throughout the WMA. As part of the HIF QA process, instruments are inspected for physical damage, the instrument must pass the ADCP diagnostic self-check tests, the temperature probe must be within ± 2 degrees Celsius of a National Institute of Standards and Technology traceable reference thermometer and the distance made good over a fixed distance must meet the manufacturer's specifications (+/-0.25% or +/-1% difference). The transform matrix is tested by conducting distance-made-good (DMG) tests comparing the straight-line distance from bottom tracking to the measured tow-track distance. The DMG test is conducted on each instrument twice in the forward and reverse directions (4 tows) at four orientations (16 total tows); with beam 1 orientated 0 degrees to the towing direction; turned 45 degrees to the towing direction; turned 90 degrees to the towing direction; and turned 135 degrees to the towing direction. All QA data files and summary results are archived. This paper documents methodology, participation and preliminary results of WMA ADCP QA testing.","PeriodicalId":356185,"journal":{"name":"2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM)","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134300086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sea state measurements in germanys first offshore wind farm \"alpha ventus\" in the south-eastern part of the north sea","authors":"Jens-G Fischer, C. Senet, Anja Schneehorst, Olaf Outzen, Sebastian Schirmel, Kai Herklotz","doi":"10.1109/CWTM.2015.7098094","DOIUrl":"https://doi.org/10.1109/CWTM.2015.7098094","url":null,"abstract":"Offshore wind farms will become more frequent in the German part of the North Sea. High and continuous wind speeds, as well as remoteness to populated areas are advantages of offshore wind turbines. To evaluate the environmental sustainability and technical/financial feasibility of offshore wind farm expansion, the German Federal Government has decided to encourage the renewable offshore sector, among other things, with a comprehensive scientific research project (Research at Alpha Ventus (RAVE)) [1]. The RAVE project startet 2008 with first marine observations 2010. Purpose of this project is to enhance the sparely investigated knowledge of impacts of the harsh marine conditions with regard to construction and operation in offshore regions. Within this project, extensive oceanographic investigations are carried out.The measured oceanographic data is a basic dataset to the entire accompanying research, both for the technical aspects as for the environmental and geological investigations. Furthermore the influences of offshore structures and facilities should be examined with respect to shelf sea physics and vice versa. The present study shows results from five years of oceanographic measurements regarding to construction and operation of offshore wind farms. For that reason the focus is on sea state observations (installation, maintenance and data analysis) which have a major impact on the operational management of offshore facilities. In this paper, measurements with directional wave rider buoys, various radar level gauges (sea state parameters calculated from water level data) and ADCPs (with option to measure sea state) are compared and evaluated to their physical limits, ambient conditions, accuracies, as well as technical advantages and disadvantages. A better understanding of the instruments helps to optimize the measurement concepts in terms of type, number, measurement time and locations. In consequence this can lead to an improvement of offshore energy production facility design, robustness and dimensioning. Additional benefits can be an optimization of facility locations and access times during facility construction and maintenance, cost reduction as well as improved energy production rates.","PeriodicalId":356185,"journal":{"name":"2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133543098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ADCP bias and stokes drift in AUV-based measurements","authors":"A. Amador, G. Pawlak, S. Jaramillo","doi":"10.1109/CWTM.2015.7098146","DOIUrl":"https://doi.org/10.1109/CWTM.2015.7098146","url":null,"abstract":"We consider the effects of surface gravity waves on AUV-based acoustic Doppler current profiler (ADCP) measurements. We present data from AUV hydrodynamic surveys in conjunction with current velocity measurements from bottom mounted ADCPs in coral reefs off the coast of Oahu, Hawaii. Transect averaged (100 m) along- and cross-track velocity measurements were calculated on a vehicle-based reference frame and compared with fixed ADCP measurements. Water velocity measurements obtained in a range of wave conditions confirm the presence of a wave-induced bias (Vbw) that is closely related to the Stokes drift. Moreover, AUV-based water velocity measurements are also subject to a wave-induced alias that results from a Doppler shifting of the measured wave velocity field. Waveinduced aliasing can enhance or suppress the bias by an amount that is proportional to the ratio of the vehicle velocity relative to the wave velocity. In addition to the wave-induced bias and consistent with a previously reported behavior, the data suggests the presence of an additional bias in the direction of the vehicle motion.","PeriodicalId":356185,"journal":{"name":"2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132694303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of polar-current-shell-based algorithm for surface current extraction from shipborne X-band nautical radar images","authors":"Chengxi Shen, Weimin Huang, E. Gill","doi":"10.1109/CWTM.2015.7098105","DOIUrl":"https://doi.org/10.1109/CWTM.2015.7098105","url":null,"abstract":"In this paper, the application of the polar-currentshell- based current inversion algorithm to shipborne X-band nautical radar images is presented. After the 3-D image spectrum is generated by a 3D-FFT of the radar image sequence, the extracted dispersion shell is converted to a polar form - the \"polar current shell\" - from which the current velocity of encounter is determined by incorporating a robust sinusoidal curve fitting. The algorithm is applied to shipborne radar data that were collected on the east Coast of Canada. The results are compared with those obtained by a WaMos system and agreement between the two indicates the validity of the proposed algorithm.","PeriodicalId":356185,"journal":{"name":"2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133862968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comparison of tilt current meters and an acoustic doppler current meter in vineyard sound, Massachusetts","authors":"N. S. Lowell, D. Walsh, J. Pohlman","doi":"10.1109/CWTM.2015.7098135","DOIUrl":"https://doi.org/10.1109/CWTM.2015.7098135","url":null,"abstract":"The relatively high cost of acoustic current meters has placed practical limits on the use of these meters in marine research projects. One approach to reducing the cost of current measurements has been the re-invention of the Tilt Current Meter (TCM). Recent developments in accelerometers, magnetometers and low-power non-volatile memory have made it possible to make small, accurate and inexpensive TCMs. Here we describe the design and calibration of the Lowell Instruments TCM and validate its performance in Vineyard Sound, Massachusetts. The performance of four TCMs was compared to an acoustic Doppler current profiler reference meter. The TCMs exhibited an R squared correlation of 0.97-0.98 as well as low slope and offset errors. Based on this demonstrated accuracy we believe the TCM would be useful for a variety of research projects especially where there is a risk of instrument loss or where increased spatial density of measurements is desired.","PeriodicalId":356185,"journal":{"name":"2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM)","volume":"242 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134041733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lithium battery safety in a flooded ADCP","authors":"B. Magnell, L. Gordon, H. Yamin","doi":"10.1109/CWTM.2015.7098127","DOIUrl":"https://doi.org/10.1109/CWTM.2015.7098127","url":null,"abstract":"Ocean deployments of battery-powered instruments often include lithium battery packs, which enable deployments to last three times as long as they would using alkaline battery packs. Lithium batteries are widely regarded as hazardous. When we discovered that one of our ADCPs, which had been deployed with lithium batteries, had flooded, we worried whether the result would pose a risk. What we found was that while the ADCP's electronics had irreparably corroded, the batteries had discharged but had not gotten particularly hot, and not much else had happened. This paper explains why things happen slowly in these lithium batteries, even when they are immersed in conductive sea water. The slow rate of discharge of these particular batteries prevents them from getting very hot in such circumstances. We conclude that these lithium batteries are probably not more dangerous than alkaline batteries, given appropriate venting of the pressure housing.","PeriodicalId":356185,"journal":{"name":"2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126050949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A vertical slice of acoustic intensity and velocity [2-D images of waves and turbulence]","authors":"Jerome A. Smith, R. Pinkel, M. Goldin","doi":"10.1109/CWTM.2015.7098151","DOIUrl":"https://doi.org/10.1109/CWTM.2015.7098151","url":null,"abstract":"Phased Array Doppler Sonars (PADS) have been developed at Scripps over the past 20 years. These provide sector-scan images of radial velocity and acoustic intensity over ranges of 0.1 m (medical ultra sound) to 1.5 km (ocean surface wave measurement). Most recently we've deployed a 200 kHz PADS from the R/V Revelle during EquatorMix (October 2012, at 140W on the Equator). The pie-shaped measurement area was oriented to probe a vertical slice under the ship parallel to the direction of travel, so that moving averages along the plane can be formed. At the surface, our speed over ground was near 1 m/s, while near 120 m depth, the core of the Equatorial Undercurrent exceeded our speed by about 0.5 m/s; i.e., the undercurrent was moving at 1.5 m/s relative to the surface, which was nearly stationary in an Earth-referenced frame. The objective was to image descending shear-layers that often occur in the early morning before sunrise, along with any associated turbulence or internal waves. Averages can be formed moving with the flow as a function of depth, yielding focused images of acoustic backscatter strength, Doppler bandwidth, and both sine- and cosine- weighted velocity estimates. Where conditions are favorable, the last pair can be recombined to yield horizontal and vertical velocities in some detail.","PeriodicalId":356185,"journal":{"name":"2015 IEEE/OES Eleveth Current, Waves and Turbulence Measurement (CWTM)","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124672155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}