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Navier-Stokes equations - Parameters ?

Started by Itay.Ro Sep 24, 2012 at 6:54 PM 3 replies 1.3k views
Original Post
Itay.Ro
Itay.Ro
I need some help wink.png
The pdf file: is Real-Time Fluid Dynamics for Games (Jos Stam) GDC 03 ..
and at page 3 of the pdf they make
6 arrays :
static u[size], v[size], u_prev[size], v_p rev[size];
static dens[size], dens_prev[size];

Dens = Density
So V=Velocity? or U? I'm dont understand what is U and V..
My English is not the best so its harder for me unsure.png

So I need to understand what is u and v and another question...
In another pdf i see that the equations have a P (Pressure) parameter so
why he didnt worte it?

Thanks biggrin.png
FLeBlanc
FLeBlanc
Velocity is a vector (2D, in this case), so it is probable that he is using the arrays u and v to store the X and Y components of the velocity vector, and u_prev/v_prev are probably storing the velocity of the previous iteration.
Itay.Ro
Itay.Ro

Velocity is a vector (2D, in this case), so it is probable that he is using the arrays u and v to store the X and Y components of the velocity vector, and u_prev/v_prev are probably storing the velocity of the previous iteration.


Thanks man smile.png
Are you sure its the x,y components and not a different variables?
FLeBlanc
FLeBlanc
Well, just xy by common convention. Some people do use uv for 2 dimensional vectors (witness uv coordinates in 3D graphics, to differentiate from xyz). It's all just personal preference.
Itay.Ro
Itay.Ro

Well, just xy by common convention. Some people do use uv for 2 dimensional vectors (witness uv coordinates in 3D graphics, to differentiate from xyz). It's all just personal preference.


Ok thanks biggrin.png
Do you know about the missing pressure parameter?

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