How can I simulate granular flows in Gazebo?

Hi, I am trying simulate a sand pile made by 1000 spheres in gazebo, which requires a lot computation time. To make it runs faster, I am considering use GPU-accelerate physics engine, PhysX, as a plugin in Ignition physics. For now, I am reading this page https://gazebosim.org/api/physics/4.1/pluginloading.html as start, but not sure if it will work well. Can I have some suggestion on this?
Otherwise, I also have an idea that just creating a fluid simulation plug-in like this https://classic.gazebosim.org/tutorials?tut=fluids&cat=physics. Bus apparently the Fluidix doesn’t support anymore. How do you simulate fluid in Gazebo nowadays?