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stock October 7, 2008 23:53

obstacle question of nasavof2d
 
hi, i recently use nasavof2d to solve tank draining problem,and i want to set obstacle cells in the fluid.so i set beta(i,j)=-1.0 in obstacle cells by hand in subroutine setup,as if (XI(I).LE.0.40.AND.(YJ(J).GE.1.0.AND.YJ(J).LE.2.0) )

BETA(I,J)=-1.0 then running the fortran codes,when i used tecplot to display the result,i found velocity appeared in the obstacle cells.. i don't understand.

thanks,stock

a October 8, 2008 01:38

Re: obstacle question of nasavof2d
 
it's not strang,

an example: assume solid is parallel to x-axis and you have no-slip condition on wall, then we set u-velocity of fictitious cells (in fact first row of obstacle, wall) equal to -1* u-velocity of cell in vicinity of wall,

i.e., for a bottom wall: u(i,j) = -1.* u(i+1,j) (e.g. for i=1)

stock October 8, 2008 03:42

Re: obstacle question of nasavof2d
 
thanks, but in the solavof2d,obstacle cells set only in the subroutine meshst as i do in the nasavof2d.it don't need to reset u-velocity or v-velocity in vicinity of obstacle wall. it only set u-velocity or v-velocity in boundary conditions.



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