# [aspect-devel] Non-dimensional temperature question

Eric Heien emheien at ucdavis.edu
Mon Mar 24 19:20:22 PDT 2014

```I’m actually referring to the values written in the statistics file (column 15) - I don’t believe non-dimensional temperature is written to the console.  I was hoping to use it for the benchmark comparison with CitcomS, but I kept getting very different values from the paper.  Is it OK if I fix it to what I wrote below?  And Katrina is correct, I should have written “the temperature difference driving convection" rather than just min/max.

-Eric

On Mar 24, 2014, at 7:10 PM, Wolfgang Bangerth <bangerth at math.tamu.edu> wrote:

> On 03/24/2014 06:50 PM, Eric Heien wrote:
>> I have a question about how non-dimensional temperature is computed in
>> postprocess/temperature_statistics.cc.  It seems the current
>> non-dimensional temperature is calculated as:
>>
>> T_nondim = (T_mean)/(T_max - T_min)
>>
>> However, suppose T_max = 4273, T_min = 973 and T_mean = 3800 (we have a hot
>> mantle).  Then the non-dimensional temperature would be
>>
>> T_nondim = 3800/(4273-973) = 1.15
>>
>> which seems to be outside the normal non-dimensional bounds of [0,1].
>> Wouldn’t the correct equation be
>>
>> T_nondim = (T_mean - T_min)/(T_max - T_min)
>>
>> in which case T_nondim would be 0.86.  Or am I misunderstanding something?
>
> You are talking about the block of text that is printed in the first time step? I've always meant to zap it precisely because of these sorts of issues. It's gotten in there very early in the development of Aspect, and I believe was added by someone who just meant to test something. I've never had the drive to remove it because I didn't want to step on others' feet. Now that someone else realizes that it's broken, would you mind just deleting the entire piece of code?
>
> Thanks
> W.
>
>
> --
> ------------------------------------------------------------------------
> Wolfgang Bangerth               email:            bangerth at math.tamu.edu
>                                www: http://www.math.tamu.edu/~bangerth/
>
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