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Paraffin wax is a prominent solid fuel for hybrid rockets. The atomization process of the paraffin wax fuel into he hybrid rocket combustion involves the droplets pinching off from the fuel surface. Therefore, droplet formation and pinch-off dynam- ics is analyzed using a one-dimensional axisymmetric approximation to understand droplet size distribution and pinch-off time. A mixed finite element formulation is used to solve the numerical problem. The computational algorithm uses adaptive mesh refinement to capture singularity and runs self-consistently to calculate droplet elongation. The code is verified using the Method of Manufactured Solution (MMS) and validated against laboratory experiments. Moreover, paraffin wax simulations are explored for varying inlet radius and it is found that the droplet size increases very slightly with the increasing inlet radius. Also, the pinch-off time increases up to a point where it starts to decrease as we increase the inlet radius. This behavior leads to a conjecture for the theoretical maximum radius that the droplet approaches as the inlet radius increases, which is a motivation for the future work.