This differntial equation:$$ \frac {k_{D_x}} {\mu_x} \left( \frac {\delta} {\delta x}  \left(\rho_x \frac {\delta P} {\delta x} \right) \right) + \frac {k_{D_y}} {\mu_y} \left( \frac {\delta} {\delta y}  \left(\rho_y \frac {\delta P} {\delta y}\right)\right) = 0 $$shall be solved.Since $\rho$ is dependent on $P$, the equation cant be simplified anymore.For my last projects I used FiPy, so do you know a method to implement this equation in FiPy?
Solving second order nonlinear ODE in FiPy
nonlinear equations;computational physics