Forum Replies Created
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The USGS has a policy where every FlowTracker is tested in a flume at the Hydrologic Instrumentation Facility when purchased, returned from repair, and at least once every 3 years.
Dave
Nick,
The export is available in QRevInt. There is a default setting in the cfg file and an option in the Options dialog.
Dave
I think having manufacturers post is a good thing provided they are not promoting or advertising. However, firmware upgrades and/or new features, instruments, software, etc. would be of interest to everybody. I don’t have an opinion on whether it needs to be in a separate subsection. If you do a new subsection I don’t know that I would break it down more the Manufacturers. Too many subsections require too many clicks to see the latest from everybody. I would rather just look in Manufacturers to see all manufacturer posts rather than having to click on each company.
Dave
I checked 10 or so RiverPro measurements and found 1 that showed this behaviour. It was even labeled bin_3.
I am guessing that it may take a specific combination of water temperature and backscatter to cause this issue.
Dave
I saw a demo at the NZHS Technical Workshop and spoke with the developer. I was impressed with both what he had developed and in talking with him, his knowledge and approach. I haven’t used one, but from the perspective of an onlooker and early developer of remote-control boats, I was very impressed.
Dave
VTG having the correct speed but the wrong direction is something I have seen in the past. It is the biggest concern when using VTG without GGA for comparison. When we evaluated the issue we couldn’t correlate when this happened with any of the GPS quality indicators. When using VTG it is recommended that the boat speed be greater than 0.24 m/s (C.R. Wagner, D.S. Mueller / Journal of Hydrology 401 (2011) 250–258) but I don’t think that guarantees this won’t happen.
If the flow is oscillating, the best approach is to collect enough transects that you capture the full range of the change one or more times depending on the duration of the change. You can then decide in post processing if you want to average transects that cover the full range for one cycle to get an overall average, or average fewer (maybe use individual transects) to define the full range and clearly show the cyclic nature of the flow. Collecting many transects and then using individual transects or an average of just a few at a time is commonly done to characterize flow in tidal environments. In your situation, the key is to collect enough transects to fully characterize the flow changes.
Dave
I would prefer they stay in the spreadsheet to maintain easy access and consistency. A post to the forum could announce the availability and provide links to any supporting documents.
Dave
Daniel,
Is this what you are looking for?
David S Mueller, PhD, PE
Genesis HydroTech LLC.
Retired from the USGS with over 35 years of experience in modeling and measuring streamflow in rivers, including over 27 years of experience using hydroacoustics for streamflow measurements. Instructed numerous training classes on the use of Acoustic Doppler Current Profilers (ADCPs) for the USGS and several international water agencies. Author or coauthor of over 70 reports and papers. The original developer of the USGS open-source software QRev, Extrap, LC, SMBA, and EDI. Now the primary developer for QRevInt and QRevIntMS.
I think putting this on the websit would be good. Perhaps an “About” button or menu item that takes you to the page. I have edited the document to reflect IHG rather than IHA and a few other edits.
Dave
SonTek does measure the screening distance from the water surface. This appears to be consistent with both RiverSurveyor and RSQ. QRev defines the excluded distance as the distance from the transducers. This definition made more sense to me as typically the excluded distance is used to remove data affected by flow disturbance, which is a function of the distance from the transducer and not from the water surface.
Dave