The goal of the proposed computational model was to evaluate the dynamical properties of air gauges in order to exploit them in such industrial applications as in-process control, form deviation measurement, dynamical measurement. The model is based on Reynolds equations complemented by the k-ε turbulence model. The boundary conditions were set in different areas (axis of the chamber, side surfaces, inlet pipeline and outlet cross-section) as Dirichlet's and Neumann's ones. The TDMA method was applied and the efficiency of the calculations was increased due to the "line-by-line" procedure. The proposed model proved to be accurate and useful for non-stationary two-dimensional flow through the air gauge measuring chamber.

Results of 3-D of discharge channel displacement simulation, acquired by means of the Fluent program during one current half-period of AC arc, indicate that the obtained images of the phenomenon are qualitatively similar to those, recorded with a high-speed digital camera, while the computer simulation enables much a more comprehensive analysis of the acquired data. In addition to selected arc simulation frames and corresponding distributions of mass velocity vectors and current density vectors on a plane, the distributions of temperature, current density and mass velocity values are presented on the axis of the electrode arrangement model. The composite motion (continuous and jumping) of discharge channels was analyzed, taking into account mass displacement and matter state changes.

The effect of multiple Rushton impellers configurations on hydrodynamics and mixing performance in a stirred tank has been investigated. Three configurations defined by one, two and three Rushton impellers are compared. Results issued from our computational fluid dynamics (CFD) code are presented here concerning fields of velocity components and viscous dissipation rate. These results confirm that the multi-impellers systems are necessary to decrease the weaken zones in each stirred tanks. The experimental results developed in this work are compared with our numerical results. The good agreement validates the numerical method.