Garg, Vivek ORCID: https://orcid.org/0000-0002-8515-4759, Deng, Tong ORCID: https://orcid.org/0000-0003-4117-4317 and Bradley, Michael (2026) Effects of relative humidity and temperature on particle adhesion measurements using mechanical surface energy tester and prediction of powder flow. Powder Technology:122502. ISSN 0032-5910 (Print), 1873-328X (Online) (doi:10.1016/j.powtec.2026.122502)

Preview

PDF (Author's Accepted Manuscript) 52794 DENG_Effects_Of_Relative_Humidity_And_Temperature_On_Particle_Adhesion_Measurements_(AAM)_2026.pdf - Accepted Version Available under License Creative Commons Attribution. Download (1MB) | Preview

Abstract

Accurate quantification of particle adhesion is essential for predicting the flow behaviour of cohesive powders, as interparticle forces strongly influence bulk powder performance. Adhesion is known to depend on environmental conditions, particularly relative humidity (RH) and temperature. This study systematically investigates the combined effects of RH and temperature on particle adhesion using a Mechanical Surface Energy Tester. The experiments enable precise control of environmental conditions, allowing adhesion forces to be evaluated under well-defined RH–temperature combinations and expressed as Bond numbers to account for particle size, shape and density effects. Fifteen pharmaceutical powders were selected to represent a broad range of particle size, morphology, and true density. Three controlled RH–temperature conditions were applied for the measurements of corresponding adhesions.
The study results show a complex, material-dependent relationship between environmental conditions and adhesion behaviour. At a low RH of 20%, adhesion generally increased, attributed to enhanced solid–solid intermolecular interactions in the absence of significant surface moisture. At an elevated RH of 80%, it found that in some cases reducing effective adhesion through lubrication effects and promoting improved flowability because of the formation of adsorbed moisture layers altered interfacial mechanics. Temperature further modulated adhesion by influencing material viscoelasticity and surface energy characteristics, leading to measurable changes of adhesions. These findings highlight the coupled influence of environmental conditions and intrinsic particle properties on adhesion behaviour. The outcomes provide valuable insights for predicting powder flow performance and for developing environmental control strategies in pharmaceutical manufacturing and other powder-handling applications.

Item Type:	Article
Uncontrolled Keywords:	particle adhesion, relative humidity, temperature, mechanical surface energy, pharmaceutical powders, flow properties
Subjects:	Q Science > QD Chemistry T Technology > TA Engineering (General). Civil engineering (General) T Technology > TJ Mechanical engineering and machinery
Faculty / School / Research Centre / Research Group:	Faculty of Engineering & Science Faculty of Engineering & Science > School of Engineering (ENG) Faculty of Engineering & Science > Wolfson Centre for Bulk Solids Handling Technology
Last Modified:	31 Mar 2026 14:14
URI:	https://gala.gre.ac.uk/id/eprint/52794

Actions (login required)

View Item

Downloads