Modelling aerodynamic forces and torques of spheroid particles in compressible flows

TL;DR

This study refines empirical formulas for aerodynamic forces and torques on spheroid particles in compressible flows through extensive numerical simulations, achieving high accuracy across a range of flow conditions.

Contribution

The paper introduces new empirical formulas for spheroid particle forces in compressible flows, validated by extensive simulations, improving prediction accuracy over existing models.

Findings

Formulas achieve less than 5% average relative error.

Strong correlation of forces with Mach, Reynolds numbers, and aspect ratio.

Formulas are consistent with incompressible flow limits.

Abstract

In the present study, we conduct numerical simulations of compressible flows around spheroid particles, for the purpose of refining empirical formulas for drag force, lift force, and pitching torque acting on them. Through an analysis of approximately a thousand numerical simulation cases spanning a wide range of Mach numbers, Reynolds numbers and particle aspect ratios, we first identify the crucial parameters that are strongly correlated with the forces and torques via Spearman correlation analysis, based on which the empirical formulas for the drag force, lift force and pitching torque coefficients are refined. The novel formulas developed for compressible flows exhibit consistency with their incompressible counterparts at low Mach number limits and, moreover, yield accurate predictions with average relative errors of less than 5%. This underscores their robustness and reliability in predicting aerodynamic loads on spheroidal particles under various flow conditions.