Numerical Simulation of Flow Disturbance on Algae Growth

Abstract

Hydrodynamic conditions have significant impact on planktonic algae growth. However, current numerical simulations rarely considered this factor. The impact of flow disturbance on algae growth rate was reviewed in this study, and laboratory experiments were conducted accordingly to find out the optimal form of velocity factor to be used in the formula of algae growth rate. A general form of velocity factor, which has clear physical meaning, was integrated into a hydrodynamic and water quality model—CE-QUAL-W2 (W2) model. The modified W2 model was applied to simulate water quality conditions in the Lower Minnesota River (LMR). Results showed that the optimal velocity for algae growth is about 0.15 m/s in the LMR, and the modified model can satisfactorily simulate algae growth process.