Hello Everyone,
I am trying to simulate flow over an airfoil and I think the example ‘externalFlowAroundObstacle’ would be the best for this task. I am very new to LBM and palabos both and I have little understanding of these topics, mainly the basics. I have a few doubts regarding this example. Currently, I have a STL file for the airfoil(which is of roughly of the same dimension as the original obstacle specified in the example) and I have edited the ‘.xml’ file and replaced the original obstacle with this airfoil.
Now, I have these doubts,
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What physical units have been used to specify the domain dimensions/velocity/viscosity etc.? In the ‘.xml’ these are only specified as some numerical quantity in physical units, but which physical unit has not been mentioned
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The Inlet Velocity has been specified as 0.1 in the original example. But is this quantity, the inlet velocity(in physical units eg m/s) or is it the Mach number? According to my understanding, an inlet velocity of 0.1 m/s doesn’t make sense. I just want to confirm if I am thinking correctly or not.
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I am confused about how can I specify my own conditions? Let’s say I want to do a simulation with standard sea level conditions (Pressure= 1.013x10^5 Pa, density=1.225 kg/m^3) and flow velocity=60m/s, then should I specify the following qunatities to the code in the ‘.xml’ file
[code=“xml”]
0.00001412 60
where nu=0.00001412 is calculated as kinematic viscosity = dynamic viscosity/density.
4. For the values given in the original example(inlet velocity = 0.1, kinematic viscosity = 0.01, sphere radius=0.05) the Reynolds number comes out to be Re = 1. But what should I do if I want to change the Reynolds number to 1000?
Basically, I want to know how I should change the values in the original xml file so that I can simulate flow over an airfoil at sea level conditions? or instead what values should I specify in the code to get the desired simulation.
Any help would be appreciated, my understanding of LBM and palabos is not very good. :-/
Thanks in advance and sorry for my band English and such a long post