[Acoustics] Simple FlowTracker question

Tue May 25 08:37:24 CDT 2004

Thank you both for these emails and would like to stay on any future
discussions that may occur with regards to using the FlowTracker.  We
are in the process of converting from cups to the acoustical doppler
flow measurement methods using the FlowTracker.  However, before we do
it we want to get us an established Standard Operating Procedure for
doing flow measurements using the FlowTracker.

If you can help us with any written SOP that the USGS uses for the
acoustical doppler flow measurements it would be greatly appreciated.
We are in the early stages of our transition but are looking forward to
shifting to the FlowTracker for replacing the pygmy and the AA meters.

Thank you in advance.

Mike

Michael H. Mosbacher, Chief

Surface and Groundwater Data Section

DWR - Central District

3251 S Street

Sacramento, CA 95816

(916) 227-7593

(916) 227-7600 Fax

-----Original Message-----
From: Michael S Rehmel [mailto:msrehmel at usgs.gov] 
Sent: Monday, May 24, 2004 12:51 PM
To: Anthony J Tallman
Cc: acoustics at simon.er.usgs.gov
Subject: Re: [Acoustics] Simple FlowTracker question

Tony, 

A FlowTracker technical memorandum will be sent out shortly which
addresses this issue. It will state: 

Location of velocity observations in each vertical - at depths below 2.5
feet, the 0.6-depth method should be used; at depths between 1.5 and 2.5
feet when a non-standard velocity distribution may be present and the
0.8 depth sample location would be more than 2 inches from any boundary,
the two-point method (0.2 and 0.8 depths) should be used; at depths
greater than 2.5 feet the two-point method should be used.  If a
non-standard velocity profile is discovered when using the two-point
method, the three-point method (0.2, 0.6, and 0.8 depths) should be
used. 

In other words, the FlowTracker gives you the ability to measure at .2
and .8 depths in less than 2.5 feet of water as long as you don't have
any boundary issues when doing the .8 measurement. If the user is
confident that the stream has a standard velocity distribution it is
left up to them to decide if they want to take advantage of this
ability. If it is possible that the profile could be non-standard a two
or three-point method should be used between depths of 1.5 and 2.5 feet
because the .6-depth method may not be representative of the mean
velocity. 

Hope this helps, 

Mike 

________________________________________________

Michael S. Rehmel                phone: 317.290.3333 ext 158
U.S. Geological Survey              fax: 317.290.3313
5957 Lakeside Blvd.               email: msrehmel at usgs.gov
Indianapolis, IN  46278             web: http://in.water.usgs.gov
________________________________________________

"Anthony J Tallman" <atallman at usgs.gov> 
Sent by: acoustics-bounces at simon.er.usgs.gov 

05/24/2004 01:50 PM 

        To:        acoustics at simon.er.usgs.gov 
        cc:         
        Subject:        [Acoustics] Simple FlowTracker question

We have recently received a FlowTracker in our office and I have a
simple 
question.  Is the FlowTracker to be treated as a pygmy or an AA meter
with 
regards as to when we switch from .6 method to .2 and .8.  I've been
told 
by two different people two different answers.

I looked in the manual, and either I missed this discussion, or it isn't

defined.

Thanks, Tony

************************************************************************
*
Anthony J. Tallman, Hydrologic Technician
U.S. Geological Survey, WRD
1289 McD Drive, Dover, DE 19901
email: atallman at usgs.gov
Voice: 302-734-2506 x223
FAX: 302-734-2964
************************************************************************
*

_______________________________________________
Acoustics mailing list
Acoustics at simon.er.usgs.gov
http://simon.er.usgs.gov/mailman/listinfo/acoustics

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://simon.er.usgs.gov/pipermail/acoustics/attachments/20040525/9f2d5f9c/attachment.html