Re: FreeSlip Boundary Condition – Implementation Doubts
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Hi Robin,rnrnThanks for your response. From your last post I have some doubts:rn

rn1. What do you mean by doing an analogue implementation ?rnrn2. The vector
n should be the normal vector in order to implement the condition grad(U)*n = 0. Maybe I did not express myself correctly in my post for the “”von Neumann boundary condition””. So in this case it is me that is wrong ;).rnrn3. I have not well understood the “”overlap”” region. But from your response, will all the nodes/lattices at the boundary be implemented to the boundary condition defined by slipboundary/velocityboundary/etc.? rnrnrnI am trying to implement the freeslip boundary condition at the boundary from the default nonlocal boundary condition based in the work of Skordos (1993). I figured out how the addVelocityBoundary from the class olb::sOnLatticeBoundaryCondition2D implements:rnrnolb::StraightFdBoundaryProcessor2D< T, Lattice, direction, orientation > Class Template ReferencernrnThis class corresponds to the algorithm proposed by Skordos. This class is used as postprocessor. The process is called from the class SuperLatticeXD in the collideAndStream() function.rnrnI would like to define a new class from StraightFdBoundaryProcessor2D class in order to redefine a new process function that will define grad(U)*n = 0. Also, I am trying to inheritance the class SuperLattice2D to add a new function addFreeSlipBoundary which will used to invoke the new class from StraightFdBoundaryProcessor2D. Basically, I want to modify the postprocess function according to what I want and then I define a new function to implement this postprocessor function, like the addVelocityBoundary function.rnrnDo you have any idea how could this could be made ? Does exist a better way to give the boundary conditions for the velocity and the grad(u) in the Skordos algorithm?rnrnBest Regards,rnrnAlejandro