[Abdelraheem]

I want to add ghost particles (mirrored in the tangent of the boundary) for every real particle within range h of the boundary with opposite velocity with same density and pressure for SPH method

[joogandomi]

Hi, Abdelraheem
What kind of ghost particle you want to use for boundary condition? Standard ghost or fix ghost?

[sina_mech]

Originally Posted by Abdelraheem

I want to add ghost particles (mirrored in the tangent of the boundary) for every real particle within range h of the boundary with opposite velocity with same density and pressure for SPH method

there are also other more efficient ways to model boundaries. Ghost particle approach usually takes more computational effort.