[tanishq1402]

I have been working on a problem related to deflagration of hydrogen-air mixture. The flame acts as a spherical wall of fixed temperature and is radially expanding. The sphere expands into the ambient so the boundary conditions on the other side are just ambient conditions at a large distance (infinity). I am unsure about how to define the radial velocity of this sphere in cartesian coordinates (how to define individual velocities of each node) and how to create a UDF for the velocities since the radial expansion varies as v = At^b. I tried to simplify this problem as a 1-D moving wall problem in cartesian coordinates but couldn't get realistic results. Any help/guidance/resource is appreciated.