.hr2 file?

Hi Nortek crew,

Thanks for the forum, a great resource.

A quick question, i updated my version of AquaPro and have noticed that now when i convert my .prf files (from an Aquadopp profiler), that within the .hdr file, there is a new file (.hr2) listed between the .v3 and .a1 files.  This file seems to simply be data from the other files, but listed together. This file would be handy as it would save the cutting and pasting, yet it is not generated by AquaPro only mentioned in the .hdr file. Should it be generating the .hr2 files?

Thanks,

Mal

Hi Mal,

The .hr2 file should only appear when you convert data collected with the HR profiler. This also applies to the list within the .hdr file. The .hr2 file contains a separate measurement , not data from the other files. I have not been able to reproduce it yet, but it looks like a software bug in the Aquapro program.

Best regards,
Oistein

Hello Oistein,

Continuing the .hr2 file discussion:

There are only 3 values for each of the following: velocities, beam counts, and correlation for each scan (measurement). So, are these values some kind of average for all the cells of a single scan (measurement) of these respective parameters? Here is an example of several lines from a .hr2 file:

01 02 2009 22 00 00.000   -0.011    0.061    0.037    62    56    71    97    76    93
01 02 2009 22 00 00.125    0.006    0.058    0.024    63    66    73    93    85    97
01 02 2009 22 00 00.250   -0.001    0.045    0.012    60    66    73    76    94    94
01 02 2009 22 00 00.375   -0.025    0.031    0.020    67    77    78    72    96    98
01 02 2009 22 00 00.500   -0.023    0.029    0.030    71    65    85    92    95    99

Best,

Ayal

Dear Ayal,

As you know the hr2 file is generated when you enable the option for extended velocity range in the instrument configuration. We extend the velocity range by placing a single measurement cell 1/3 into the profile. The hr2 file shows the measured data in this cell. Since we then also use a shorter lag, this cell gives us the velocity at this point with a factor 3 higher velocity range than the regular profile. We then use this velocity to resolve the velocities of the whole profile. You should normally not need to look at the data in the hr2 file since we have used that information already in the profile output. But if you have a data set that looks suspicious, you may want to check that the correlation in the hr2 file to see if there is a problem with the measured data from the second (higher velocity) lag.

I have attached a plot of some data that was collected during our recent User Symposium that shows some HR Profiler data collected in the surf
zone using the extended velocity range. The data are sampled at 4 Hz in 3 cm cells. The white "gaps" in the data are correlations below 40%.

Best regards,
Sven

Hello Sven,

Thanks for the info. In fact I didn't know what/when the .hr2 is generated. I suggest something to this effect be added to the Aquadopp HR user guide. BTW, the version of this guide, which comes with the HR Aquapro software, is May 2008. (Apparently there is no HR manual as such on Nortek's website, i.e. at http://www.nortek-as.com/support/manuals.)

Hello Ayal,

I have added more information on the extended velocity range here: Re: ambiguity jumps in AquaDopp HR

Best regards,

Sven