Flow In Stirred Vessel Research Articles

Simulation of the Fluid Flow in Stirred Vessels Using MPS Method with the Integral Wall Model

Simulation of the Fluid Flow in Stirred Vessels Using MPS Method with the Integral Wall Model

Numerical Simulation of Particle Mixing Feature for a Gas-Liquid-Solid Three Phase Flow in an Impeller-Driven Stirred Vessel

In this work, numerical simulations have been conducted to investigate the particle mixing feature in a stirred vessel driven by an impeller. The Eulerian multi-fluid model has been employed along with the standard k–ε turbulence model to simulate the gas-liquid-solid three-phase flow in the stirred vessel. The effects of impeller speed and immersion depth of impeller on the particle distribution are discussed. The results show that the particle volume fractions nearby the vessel bottom are large on the vicinity of the side walls of the vessel and small in the vessel middle region at different impeller speeds and immersion depths.

Characterization of Gas−Liquid Flows in Stirred Vessels Using Pressure and Torque Fluctuations

Gas-liquid flows in a stirred vessel exhibit different flow regimes and demonstrate complex interaction of transport processes with varying spatio-temporal scales. The knowledge of key space and time scales of fluid dynamics is important for designing and enhancing the performance of gas-liquid stirred reactor. The present study uses simple, robust, and nonintrusive experimental techniques (torque and pressure sensors) to characterize the fluid dynamics in a gas-liquid stirred vessel. Time series obtained from the pressure and torque sensors were analyzed to develop criteria for flow regime identification. Further analyses of torque and pressure time series were done to extract valuable information of different time scales of fluid dynamics. The detailed analysis of torque and wall pressure fluctuations provided not only an insight into the fluid dynamics but also a possible opportunity to on-line monitoring of gas-liquid flows in stirred vessel.

Simulation of Flow in Stirred Vessel with Axial Flow Impeller: Zonal Modeling and Optimization of Parameters

The usefulness of the turbulent k-ε model for simulation of flow in a stirred vessel was studied in detail. For optimization, the effects of model parameters on flow characteristics were analyzed. It was observed that, any single set of model parameters could not yield even reasonable agreement between the model predictions and the experimental observations throughout the vessel. Therefore, the concept of zonal modeling was introduced for the r-z plane. It was observed that with the introduction of zonal modeling, the predicted values of flow variables, except the energy dissipation rate, were in good agreement with experimental data even close to the top surface of the tank. The same results could not be obtained with the standard set of parameters and a single zone. Local turbulent energy dissipation rate (ε) was calculated using the expression (ε = k3/2/Lres) proposed by Wu and Patterson (1989). The zonal modeling prediction was better than the prediction by a standard set of parameters. However, above the impeller, a wide discrepancy between the predicted and experimental value for energy dissipation rate was observed.