Lumped-parameter modeling fluid and thermal systems

We now consider the lumped-parameter modeling of fluid systems and thermal systems. The linear graph-based, state-space modeling techniques of , , are called back up to service for this purpose. Recall that this method defines several types of discrete elements in an energy domain—in , , the electrical and mechanical energy domains. Also recall from that energy transducing elements allow energy to flow among domains. In this chapter, we introduce fluid and thermal energy domains and discrete and transducing elements associated therewith.

The analogs between the mechanical and electrical systems from are expanded to include fluid and thermal systems. This generalization allows us to include, in addition to electromechanical systems, inter-domain systems including electrical, mechanical, fluid, and thermal systems.

This chapter begins by defining discrete lumped-parameter elements for fluid and thermal systems. We then categorize these into energy source, energy storage (A-type and T-type), and energy dissapative (D-type) elements, allowing us to immediately construct linear graphs and normal trees in the manner of . Then we can directly apply the methods of to construct state-space models of systems that include fluid and thermal elements.