Solver Modes - Reflection Advection
Reflection advection solver mode is based on the paper titled An Advection-Reflection Solver for Detail-Preserving Fluid Simulation presented at Siggraph 2018. You can find the link to the paper here.
What it does is conserve energy lost when you perform the project-non-divergent step on the velocity field. The technique achieves this by advecting and projecting velocity two times with a corrective step in the middle that helps conserve some of the lost energy.
You can enable this solver mode by going to the Solver -> Settings -> Solver Mode drop down menu on the solver HDA and selecting “Reflective“.
Below you can see some examples of reflection advection versus traditional advection below.