Simulate with complex geometries and complex physics
ImplicitEuler
This algorithm solves the semi-discrete ODE-system
\begin{align} \mathbf{\dot{U}}(t) = \mathbf{F}(t,\mathbf{U}(t))\end{align}
with the implicit Euler method which is of order 1:
\begin{align}
\mathbf{U}^{k+1} = \mathbf{U}^k + \Delta t \, \mathbf{F}\big(t^k + \Delta t, \, \mathbf{U}^{k+1} \big)
\end{align}
The ODE-system comes from the spatial discretization of velocity and pressure in solve_V_2.
Both vp- and v-- can be solved.
The time integration scheme can be controlled by time_integration_impl and resp. for the velocity by time_integration_impl_solve_v.