pressure -> dragforces

hulli · January 19, 2018, 10:42

Hi all,

I am trying to derive the drag and lift forces from my simulation with paraview (extract surfaces and compute the normals). So far I found out that p is given in (m^2/s^2) and needs to be multiplied by the density (1000 in my case), which will give me pascals. Then multiplying the static pressure times the normal I end up with the drag/lift forces.
I am somewhat confused now, with regard to the pressure because it is way lower that the hydrostatic pressure that I expected in the domain. In addition to that the drag forces are quite low. So I was wondering if I need to add the atmospheric pressure to that computation in order to end up with “physical results”? Or do I need the total pressure to calculate lift and drag ?

I high appreciate any help

Thank you so much

Best H

Tobi · January 24, 2018, 09:08

I guess you are the same person than in the German OpenFOAM forum right? Thus, the problem should be solved, or not?

January 19, 2018, 10:42	pressure -> dragforces	#1
hulli Member hulli graemer Join Date: Oct 2014 Posts: 48 Rep Power: 11	Hi all, I am trying to derive the drag and lift forces from my simulation with paraview (extract surfaces and compute the normals). So far I found out that p is given in (m^2/s^2) and needs to be multiplied by the density (1000 in my case), which will give me pascals. Then multiplying the static pressure times the normal I end up with the drag/lift forces. I am somewhat confused now, with regard to the pressure because it is way lower that the hydrostatic pressure that I expected in the domain. In addition to that the drag forces are quite low. So I was wondering if I need to add the atmospheric pressure to that computation in order to end up with “physical results”? Or do I need the total pressure to calculate lift and drag ? I high appreciate any help Thank you so much Best H

January 24, 2018, 09:08		#2
Tobi Super Moderator Tobias Holzmann Join Date: Oct 2010 Location: Tussenhausen Posts: 2,708 Blog Entries: 6 Rep Power: 51	I guess you are the same person than in the German OpenFOAM forum right? Thus, the problem should be solved, or not? __________________ Keep foaming, Tobias Holzmann

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