Modeling and Simulation of Aquaculture Systems.

Abstract

In this work, models for aquaculture are developed with regard to their relevance in an automated recirculation system. The three subsystems fish, water, and feed are determined as modular components. A selection of relevant variables is determined. The relationships between feed, water quality, and fish growth are described on the basis of an initially qualitative description (causal network) and quantified using ODEs. The considered water treatment systems and control devices are used to describe the relationships between filtration, fresh water addition, and water quality. The numerical system model allows simulations of the overall system behavior in time domain including the full growth phase offish. As example, the conditions using rainbow trout are simulated in a recirculating system. Influences of different variables like water temperature, pH-value, or protein content in dependency of the fish feed variables are shown, as well as the influence of plant parameters. This allows a recording of water quality and also to monitor the optimal fish growth or well-being parameters. The developed model can be extended modularly and allows further considerations and analyses for the control of the plant volume flow or for carbon dioxide gassing.