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Reply To: Low Density Simulation


Dear Sahil,

generally, it is a good idea to set the initial lattice density to unity, as described in the book you referred to. You will find this very approach in most of our examples. Your usage of the OpenLB methodology seems to be correct.
The density derived from the first moment of the distribution function, however, will change during your simulation. In order to end up with a pressure difference in a force free flow you need to have some proper boundary conditions applied to your walls. It might be a good idea to start with a common setup of velocity inflow, pressure outflow and no-slip wall condition first and see whether the expected pressure drop can be observed, both reflected by the console output and the VTK writout. You can then adapt this to a double velocity condition setup and see, whether your issues still persist.