An experimental investigation on the fluid flow mixing process in agitated vessel

Abstract

The fluid mixing process is a common supportive phenomenon that often occurs in a large number of industrial systems. This phenomenon is the subject of many numerical and experimental analysis. The mixing process effectiveness depends on: mixing tank construction, mixing phases viscosity, temperature, density of liquids and, what is crucial, the impeller shape. The optimal design of impeller geometry is still an open issue. In this research work, the main objective is experimental investigations of the influence of the newly constructed impeller type on the fluid flow motion phenomena and energy consumption. Flow field values were evaluated using PIV measurement and the power consumption using precise torquemeter. The comparison between the Rushton turbine and a novel impeller is presented and discussed. The basis for the assessment of the intensity degree and efficiency of mixing was the analysis of velocity vectors distribution and power number. Results show that the power number for both impellers are similar but the fluid motion is quite different. The pumping capacity Qz for the novel impeller in reference to the Rushton turbine is for many cases at least one order of magnitude higher. This shows that the proposed impeller can be a very promising alternative to the classic blades and non-blades based impeller types.

Impact of baffle geometry on the fluid motion in the stirred vessel

“…The of PIV measurement described in detail in the paper Młynarczykowska et all. [12] In the final step of experimental analysis based on the results two keys criteria numbers were evaluated: Power number Np and Reynolds number Re. Those parameters designated according to the equations:…”

A General Review of the Current Development of Mechanically Agitated Vessels

“…The simulation results showed that flow pattern and dimensionless velocity distribution are related to Reynolds number and regime type without change values in the turbulent regime. The lowest drop of total power number for single and parallel configuration of the impellers was observed in laminar regime [5,6,78,79,164]. A large number of researchers have performed numerical simulations to examine the impact of impeller geometry on the mixing process in order to find optimal configuration, low mixing time or low power consumption [165][166][167].…”

“…the internal vessel geometry or configuration (baffles, coils, vessel bottom type, etc. [3][4][5][6]); -the fluid properties (densities, number of phases, a viscosity [7]);…”