I am dealing with a PDE which can be written in the form
$$\frac{d}{dt} f(t) = \{a, f(t)\} + \{\{b, f(t)\}, f(t)\}$$
A Hamiltonian equation on a Poisson manifold has the following form: $$\frac{d}{dt} f(t) = \{a, f(t)\}$$
My equation seems to be a sort of "quadratic" Hamiltonian evolution. I hope that there exists some theory (existence, uniqueness, etc.) of such equations on Poisson manifolds which leverages the present algebraic structure.
I suppose even more generally one could study equations of the form $$\frac{d}{dt} f(t) = \sum_{k=0}^n \{ \dots \{a_k, \underset{k}{\underbrace{f\}, \dots, f\}}}$$.
If one says that the Hamiltonian evolution is the simplest possible ODE one could study on a Poisson manifold, then clearly these equations come right after that in terms of simplicity and naturality.