Analysis of Mixing Capability in Stirred Tank Reactor Using Computational Fluid Dynamics
Keywords:
Stirred tank reactor, CFD, Turbulence model, MixingAbstract
The Stirred Tank Reactor (STR) is widely used in the industry. Understanding the flow characteristics within the tank is important in determining the performance of the mixing process. The objective of this paper presents the study of the flow characteristics and velocity distribution of fluid within the Stirred Tank Reactor (STR) using 8 blades Rushton turbines in the middle of the tank to drive. Calculate the flow results using Computational Fluid Dynamics (CFD). The Large Eddy Simulation (LES) using to capture the turbulence and the Sliding Mesh technique (SM) to simulate the impeller motion. The study of mixing characteristics at impeller speeds of 100, 200, and 300 rpm. The study results showed that the tangent velocity generated vortex flow around the shaft within the stirring tank. When continuous mixing, the flow characteristics will be steady-state. This flow characteristic affects the mixing capability of the process that requires turbulence for the mass transfer between the fluids. However maintaining turbulence in the mixing process required high energy.
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