Coupled heat transfer - H transport (transient)

[RemDelaporteMathurin]

Something like this:

class CoupledHeatTransferHTransport():
    h_transport_problem: HydrogenTransportProblem
    heat_transfer_problem: HeatTransferProblem

    def initialise():
        self.h_transport_problem.initialise()
        self.heat_transfer_problem.initialise()

        self.h_transport_problem.T = self.heat_transfer_problem.u

    def iterate():
        self.h_transport_problem.iterate()
        self.heat_transfer_problem.iterate()

        next_dt_value = min(self.h_transport_problem.dt, self.heat_transfer_problem.dt)
        self.h_transport_problem.dt = next_dt_value
        self.heat_transfer_problem.dt = next_dt_value