抄録
A two-phase hydrodynamic model was used to calculate the distribution of gas volume fraction in an aeration tank equipped with diffused aeration system. The calculated gas fraction distribution was used to estimate the volumetric oxygen transfer coefficient (K_La) in the aeration tank. For modelling the turbulence in the liquid phase, k-ε model was used, while gas phase was modeled as laminar. 2-D simulations were performed for 5 full-scale and 5 pilot-scale aeration tanks having different tank configurations and diffuser positions. Under different conditions, the measured liquid surface velocities and were found to compare well with the prediction of hydrodynamic model. DO concentration was also calculated by defining a scalar transport equation.