Due to recent bot attacks we have changed the sign-up process. If you want to participate in our forum please send a message via our contact form. › Forums › Lattice Boltzmann Methods › General Topics › Permeability Calculation Poiseuille › Reply To: Permeability Calculation Poiseuille April 24, 2019 at 2:49 pm #4265 fkParticipant The code looks mostly fine, but try to smooth pin: AnalyticalConst2D<T,T> rho(converter.getLatticeDensityFromPhysPressure(frac[0]*pin));