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TOPIC: Dynamic Pressure - UNIT in Result file

Dynamic Pressure - UNIT in Result file 7 years 4 months ago #27104

  • sathya
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Hello,

I have simulated the 3d problem and obtained the result.

The 3dresult file contains the following
U,V,W,DP

Here DP = Dynamic Pressure



I am not clear with the unit of DP in the result file.

In the DICTIONARY File, The explanation is given as
DP is multiplied by (DT/RHO)


So, What is the unit of DP which is written in the result file?
Is it Pa?
or
Is it Pa times (DT/RHO)?



Regards
Vks
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Dynamic Pressure - UNIT in Result file 7 years 4 months ago #27116

  • jose2kk
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Hello Vks,

In BK to see the output variables units:
1. Right click on any variable.
2. Select properties.
3. Go to tab 'Data'.

Once there, you can see the units, as well as Max and Min values.

I hope this helps.

Cheers,
José Andrés.
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Dynamic Pressure - UNIT in Result file 7 years 4 months ago #27117

  • Phelype
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Hello Vks,

In the prediv.f subroutine it says that
!+ THE PHYSICAL DYNAMIC PRESSURE IS OBTAINED BY MULTIPLYING: PD*(RHO/DT)

So {Pa}={Unit-of-DP}*({Kg/m³}/{s})

So {Unit-of-DP} should be {m²/s}, if I did the maths correctly and if this is the actual variable saved to the file.

Hope it helps.

Best regards,

Phelype
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Dynamic Pressure - UNIT in Result file 7 years 4 months ago #27118

  • jose2kk
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Hello,

I ran an example (t3d/bump) and the results gives [DP-unit]=[Pa].

Phelype, I tought the same as you at the beginning. However, I took a deeper look at the manual and RHO is the relative density and not the density.

Hope this helps.

Cheers,
José Andrés.
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Dynamic Pressure - UNIT in Result file 7 years 4 months ago #27119

  • sathya
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Hello,
Thanks for your reply.


Can you help me in calculating the DP(multiplied by (DT/RHO)) by taking velocity as 0.000123408 m/s ?
Just formula and substituition is enough.

Thanks
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