What is the unit of dimensional force?

ceanwang · August 15, 2018, 05:12

Hi,

In Forces_breakdown.dat I get:

Forces breakdown:

Center of Pressure: X=0.426311Z+5399.999366 m.

NOTE: Multiply forces by the non-dimensional factor: 50000000.000000, and the reference factor: 1418.550000
to obtain the dimensional force.

Total CL: 0.707787 | Pressure ( 99%): 0.707787 | Friction ( 0%): 0.000000 | Momentum ( 0%): 0.000000
Total CD: 0.301737 | Pressure ( 99%): 0.301737 | Friction ( 0%): 0.000000 | Momentum ( 0%): 0.000000
Total CSF: -0.000952 | Pressure ( 100%): -0.000952 | Friction ( 0%): 0.000000 | Momentum ( 0%): 0.000000

Take Drag as example:

Drag= 0.301737 * 50000000.000000 * 1418.550000

What's the unit of it? N,kN?

Thanks for help.

Regards,

Cean

pcg · August 15, 2018, 05:56

If you use SU2 in SI units the force is in Newton.

ceanwang · August 15, 2018, 08:43

thank you very much.

after using the correct unit, even the incomp caculation can reach convergence.

August 15, 2018, 05:12	What is the unit of dimensional force?	#1
ceanwang Member cean wang Join Date: Feb 2013 Posts: 43 Rep Power: 13	Hi, In Forces_breakdown.dat I get: Forces breakdown: Center of Pressure: X=0.426311Z+5399.999366 m. NOTE: Multiply forces by the non-dimensional factor: 50000000.000000, and the reference factor: 1418.550000 to obtain the dimensional force. Total CL: 0.707787 \| Pressure ( 99%): 0.707787 \| Friction ( 0%): 0.000000 \| Momentum ( 0%): 0.000000 Total CD: 0.301737 \| Pressure ( 99%): 0.301737 \| Friction ( 0%): 0.000000 \| Momentum ( 0%): 0.000000 Total CSF: -0.000952 \| Pressure ( 100%): -0.000952 \| Friction ( 0%): 0.000000 \| Momentum ( 0%): 0.000000 Take Drag as example: Drag= 0.301737 * 50000000.000000 * 1418.550000 What's the unit of it? N,kN? Thanks for help. Regards, Cean

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August 15, 2018, 05:56		#2
pcg Senior Member Pedro Gomes Join Date: Dec 2017 Posts: 466 Rep Power: 13	If you use SU2 in SI units the force is in Newton.

August 15, 2018, 08:43		#3
ceanwang Member cean wang Join Date: Feb 2013 Posts: 43 Rep Power: 13	thank you very much. after using the correct unit, even the incomp caculation can reach convergence.