Ok
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This is for some kind of conventional lattice wing. Where is the difference between the calculation and the conducted experiment shown
sup boys, any good news yet?
For?
SpaceX’s N1 Starship went away with the folding mechanism for the grid fins and just flies with them fully extended now. If we go back to the argument that these are airbrakes and nothing else… then their argument is less and less supported as of late.
Even more - with the grid fins extended on the booster stage, the rocket becomes somewhat unstable and requires a lot of engine gimbal if the drag is so high. The drag center being in front of the center of mass should cause the missile to lose control… but it doesn’t. This is because the grid fins do not cause nearly as much drag as people assume. Who would have thought that a porous object is less draggy than a completely solid one.
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I’m still in the process of researching. So far the grid wings are hard to figure out
I was just saying this because previously people claimed the Falcon solely used the grid fins for airbrakes and not for steering… which was somewhat absurd. If that was the case the new Starship would have kept the foldable fins and not left them deployed from launch until landing.
Will be nice to see what you find when you’re complete with the CFD.
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This is not safe to use without a flared base.
What are you going to use for the CFD? Ansys, OpenFoam or something else?
I assume then you use Ansys also for the mesh then… How will you do the inflation for the grind fins? Because sharp close edges can be annoying. Or do you just not do the inflation entirely and just use triangular on the edge?
I create the grid in the same place, the edges of the grid fins edges are made sharp so that the grid lies normally
oh ok that makes sense, what cell size did you use though? Cause without inflation it can get very heavy to calculate if the grids is too thin. Although for warthunder modelling purpose even if not super precise it would be fine
The total number of cells is 7.5M
Yeah since it is only a missile the total number number seems fine, what I meant is the general cell size and the sizing min values:
I was curious about the parameters in red
I don’t remember exactly, it seemed to be 1 mm
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how much time is this taking you?
Quite a lot, after all, the computing power is small. I9-10940x 128Gb RAM