∗ Low Mach hydro
pyro's low Mach hydrodynamics solver is designed for atmospheric flows. It captures the effects of stratification on a fluid element by enforcing a divergence constraint on the velocity field. Chapter 14 of the notes describe the basic algorithm:
As with the incompressible solver, we implement a cell-centered approximate projection method.
The bubble problem places a buoyant bubble in a stratified atmosphere and watches the development of the roll-up due to shear as it rises. This is run as:
./pyro.py lm_atm bubble inputs.bubble