Bond Graphs in Modeling Plant Water Dynamics


The objective of this research was to apply the bond graph representation to models describing plant processes. Two models that deal with the water dynamics of vegetation were chosen. One describes the water dynamics within the plant, called the hydraulic flow model, the other describes the energy fluxes into and out of the system plant.

The hydraulic flow model is a mechanistic model used to study the movement and storage of water in different plant organs, as well as overall water movement through the plant. It was put in bond graph notation and applied to a study of an agave plant. The energy balance of a plant considers the energy fluxes into and out of heat and metabolic storages. In ecology, it is used to analyze the relations between net radiation, and latent as well as sensible heat fluxes. A bond graph has been developed for this purpose and has been implemented in Dymola using models found in ecology for the description of radiation input, as well as the stomatal and boundary layer conductance of heat and mass transfers.