Assessment of mathematical expressions for morphological parameters of solid particles based on common geometric shapes

Abstract Particulate solids or fragments are found in nature and many industrial processes. They are commonly characterized by a number of morphological parameters, for which the mathematical expressions in literature usually come from comparisons to idealized shapes. Whereas these expressions must fit some requirements firstly on common geometric shapes before being used on a real solid particle. In this work, the expressions for calculating morphological parameters based on both projected area (2D) and on three-dimensional (3D) shapes of solid particles were evaluated. Hereof expressions from literature related to the same morphological parameter were identified, and others defined originally on projected area, 2D, were proposed to be used on 3D shapes. The results allowed to indicate the most suitable expression for each parameter based on pre-established criteria. In practice, distinct values obtained from different expressions applied to the same shape make a comparative analysis a complex task, which requests commitment for Standardization.