3D uniformity measurement of stirring system based on dual-camera positioning

Abstract

This investigation proposes a dual-camera positioning method and the average distance in the cube (AD-Cube) method to explore the effect of three-dimensional (3D) spatial multiphase stirring. The 3D trajectories of the tracer ball were reconstructed in the stirring system using a dual-camera positioning method. The AD-Cube method for calculating the mixing uniformity within the cube region was proposed and verified by rigorous and valid numerical validation (the standard reference value was approximately 0.6617). The negative correlation coefficient between conductometry and the AD-Cube method for the evaluation of the mixing effect was −0.9118. The stirring region was equally divided into several 3D blocks, and the relationship between the whole and local was elaborated to provide more accurate information for the 3D uniformity metric. Moreover, the volume of the stirring dead zone was estimated by discrete blocking, and the influence of the stirring paddle height from the bottom and agitating motor speed on the stirring effect was studied. This study provides a theoretical basis for optimizing the parameters of a 3D stirring system, designing chemical reactors, and measuring and evaluating the 3D uniformity of stirring systems. • The proposed method is based on dual-camera positioning and computational geometry. • The 3D uniformity of stirring system is characterized by the novel method. • Effectiveness of the novel method is verified on both numerical and experimental. • Evaluation indicator is established to evaluate the 3D stirring efficiency. • The method can be used in engineering fields of evaluation of 3D uniformity.