№82-16

System analysis of design features of air centrifugal classifiers and prospects for their improvement

A. Khrutskyi¹,  https://orcid.org/0000-0002-9332-1748

M. Franuzo¹    https://orcid.org/0009-0003-4354-0875

¹Kryvyi Rih National University, Kryvyi Rih, Ukraine

Coll.res.pap.nat.min.univ. 2025, 82:183-195

Full text (PDF)

https://doi.org/10.33271/crpnmu/82.183

ABSTRACT

Purpose. To conduct a systematic analysis and generalization of the structural features of dynamic centrifugal air classifiers in order to identify typical and rare parameters, interrelations, and patterns of their geometric and functional evolution, with the aim of developing recommendations for the design, modernization, and selection of equipment for the classification of fine and ultrafine materials.

The methods. Sixty-eight designs described by ten parameters were studied. Principal Component Analysis (PCA) was applied for dimensionality reduction and visualization, and DBSCAN clustering was used to identify groups. An evolution tree of the working element – the air flow – was constructed.

Findings. A systematic analysis and generalization of the structural features of dynamic centrifugal air classifiers were carried out. It was determined that the most common designs have: a vertical axis (92.6%), a cylindrical housing (86.8%), and dynamic blades (66%). Typical combinations account for ≤16% of models, indicating significant diversity. Two principal components explain 71.04% of the variance. DBSCAN identified 4 groups and one atypical design. Correlations were found: air circulation is always accompanied by flat rotating blades; horizontal models only have centrifugal wheels or none; static designs have no additional air supply. Two promising designs were identified – an existing one (snail-shaped housing, vertical axis) and a hypothetical one (snail-shaped housing, horizontal axis). The evolutionary tree illustrates the development of the working unit of centrifugal air separators.

The originality. For the first time, a comprehensive multidimensional analysis of classifiers was performed using PCA and DBSCAN, systematizing designs and patterns of their evolution, and proposing a development tree of the working element.

Practical implementation. Optimization of designs can improve efficiency, reduce energy consumption and wear, integrate recommendations into CAD/CAM systems, and serve as a basis for CFD modeling.

Keywords: mineral beneficiation, air centrifugal classifiers, parameters of centrifugal classifiers, frequency distribution of parameters, dimensionality reduction, clustering, systematic analysis, evolution tree, air flow.

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