In this questionquestion, I suggested that the Couran-Friedrichs-Lewy (CFL) condition for the wave equation in polar coordinates reads
$$C = 2c\frac{\Delta t}{\Delta r \Delta \phi} \leq C_\max \enspace ,$$
where $c$ is the phase speed. I suggested this from an intuitive point of view, and it worked in that example. Nevertheless, This is probably not right, And I could not find an expression for this case.
Question: What is the CFL condition in polar coordinates?
This question was asked before in Math.SE:
- Harley (https://math.stackexchange.com/users/357049/harley), CFL condition in polar coordinates., URL (version: 2016-07-31): https://math.stackexchange.com/q/1874881