New to LBM and OpenLB? Attend our upcoming one-week hands-on Spring School in Marseille/France from 19.05.2025 – 23.05.2025. OpenLB – Open Source Lattice Boltzmann Code › Forums › on OpenLB › General Topics › Advection Diffusion moddelling › Reply To: Advection Diffusion moddelling November 6, 2024 at 10:54 am #9486 mathiasKeymaster It might be that you need a second internal velocity also be initialized..