Contact Forces Between Drug Particles and Container Wall Are Now Better Understood

Achievement date: 
2013
Outcome/accomplishment: 

Through a series of computationally intensive simulations, researchers at the NSF-funded Engineering Research Center (ERC) for Structured Organic Particulate Systems (CSOPS) headquartered at Rutgers, The State University of New Jersey, have gained a greater understanding of contact forces—specifically interactions between particles and walls, within confined granular systems.

Impact/benefits: 

In particulate systems, there exists a great deal of ambiguity and debate with regard to mathematical behavior at high densities. Furthermore, these interactions have never been reported at high confinement, at which near-wall and particle-wall interactions deviate greatly from the bulk. By employing a novel and complex methodology, the CSOPS researchers have been able to successfully predict the behavior of particles under such conditions.

Explanation/Background: 

Current methods for calculating and simulating particle-wall interactions have major shortcomings and are not readily reliable in industry. Macroscopic external effects, such as the pressure in the pressing phase of oral medication tablets, can have a profound effect on the behavior of granular compounds. However, current methodologies cannot accurately account for this phenomenon. There has been debate over whether behavior at high confinement is best represented as Gaussian or exponential decay. This work clearly demonstrates that the behavior transitions from exponential to Gaussian.