Dr. Muhammad Akashi who is working with Prof. Doron Chelouche has been running FLASH code models to simulate the formation and evolution of planetary nebulae formed by aging stars.

Link: http://hivehpc.haifa.ac.il/images/dens3D.png

The above picture shows the density structure of the planetary nebula expanding out from three interacting stars. It's the first time such a calculation has been done with such detail, and what we see is a particular frame in time, for a particular projection of the (three-dimensional) nebula.
For comparison, A real planetary nebula, as seen in space is looking like that:

Source of the picture: http://www.esa.int












Link(source: www.esa.int ): http://www.esa.int/var/esa/storage/images/esa_multimedia/images/2015/07/born-again_planetary_nebula/15533530-1-eng-GB/Born-again_planetary_nebula.jpg

These results have just been presented in a big meeting on the physics of planetary nebulae by Muhammad in China.