Solids volume fraction measurements on riser flow using a temporal-histogram based DIA method

In this article we introduce a temporal histogram-based method for digital image analysis (DIA) of pseudo-2D fluidized bed risers. This method enables an accurate whole field measurement of the solids volume fraction in lab-scale pseudo-2D riser flows by successfully removing image imperfections and merely accounting for the particles' intensity. Moreover, the new correlation between normalized intensity and solids volume fraction that is proposed in this work enables a quantitative approach for solids concentration measurements by DIA techniques. This technique can be easily adjusted with experimental settings and shows a great stability against adverse imaging conditions. The combination of this parameter-free method with particle image velocimetry under riser flow conditions has been successfully applied, enabling the experimental acquisition of full field hydrodynamic dat