1. Link graphs. Thermodynamics

Link graphs are based on an energetic expression of the dynamics of physical systems. A system is divided into components, and the system's link graph indicates how energy is exchanged between components. A component model indicates how energy is stored, modified or degraded within the component.

• First principle: temporal continuity of energy

  The first principle of thermodynamics expresses the conservation of energy. Thus, energy storage indicates a memory effect. Since the physical systems used by engineers can always be broken down into a continuum of micro-systems that also verify the first principle, we can legitimately assume the spatial conservation of energy. A variation in energy at one point in the system must correspond to a flow of energy from another point in the system (except for energy sources)....