Modeling of Aircraft Propulsion Systems Through Graph Theory

The increasing complexity of electrified propulsion systems for aviation requires scalable and generalizable models to support design activities exploring the potential of new enabling technologies. Traditional computational frameworks rely on predefined architectures and hybridization factors, limiting flexibility when introducing novel powertrain configurations. This paper proposes a computational framework for modeling propulsion systems based on graph theory, offering a topological representation capable of describing virtually any acyclic powertrain. In the proposed approach, system components are represented as vertices connected by directed edges that define power flows. The resulting acyclic directed graphs enable consistent and modular descriptions of systems with multiple energy sources, including fuel, battery, and hydrogen-based configurations. Thus, the computational framework defined in this work can be applied to any propulsion system presented in the literature without major changes. Furthermore, new parameters are introduced to represent the contribution of the power sources to each propulsive line, which provides the designer with greater control over the distribution to explore alternatives in the power distribution that have been neglected in previous works. Finally, the method is not prone to singularities common in conventional formulations.