Vibrations in engineering and technology

Dmytriv Ihor - Candidate of Technical Sciences, Associate Professor, Associate Professor of the Department of Automotive Transport, Lviv Polytechnic National University, 79013, 12 Stepan Bandera Str., Lviv, Ukraine, е-mail: Ihor.V.Dmytriv@lpnu.ua,  http://orcid.org/0000-0002-5107-7273

Sahan Oleh - recipient of the PhD degree of Department of Desing Machine and Automotive Engineering, Lviv Polytechnic National University, 79013, 12 Stepan Bandera Str., Lviv, Ukraine, е-mail: Oleh.Y.Sahan@lpnu.ua, https://orcid.org/0009-0004-5116-8679

The paper presents the results of an experimental study of multicomponent bulk-material mixing in a continuous centrifugal dispenser–mixer. The objective was to quantitatively evaluate mixture homogeneity and to determine how key design and operating parameters affect mixing quality by combining classical statistical indicators with digital image analysis. To test the hypothesis that the mixer can ensure a high level of homogeneity, a planned three-factor experiment was carried out by varying the dosing disk rotational speed, the disk generatrix angle, and the excess pressure in the working zone.

The assessment procedure relied on introducing color markers for each mixture component, taking control samples after mixing, and photographing them under fixed lighting conditions and a fixed camera geometry. Image processing included correction of the captured frames, color-based segmentation, estimation of component fractions within the image, and statistical aggregation across measurement series. Based on the resulting dataset, integral homogeneity indicators were calculated and compared for different combinations of factors, which made it possible to identify characteristic trends in mixing quality depending on the operating mode.

The experimental results demonstrate a consistently high level of mixing across a wide range of operating conditions, while the influence of the investigated parameters follows a regular pattern, providing a basis for further optimization of the design and settings. The proposed approach not only confirms the efficiency of the centrifugal dispenser–mixer but also establishes a reproducible method for quantitative mixing-quality evaluation based on digital images. The findings can be applied in the food, pharmaceutical, chemical, and construction industries, as well as for laboratory quality control and process analytical technology tasks.

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