Configurational Forces in Penetration Processes

TL;DR

This paper investigates the role of configurational forces during penetration processes, such as nanoparticle entry into cells, revealing how these forces influence the insertion and expulsion of compliant intruders in elastic structures.

Contribution

It introduces a theoretical analysis of configurational forces in penetration, accounting for both rigid and compliant constraints, highlighting their effect on penetration dynamics.

Findings

Configurational force proportional to strain squared in rigid constraints

Complex structure of forces when constraint compliance is considered

Forces tend to expel the penetrating body

Abstract

With a loose reference to problems of penetration in biomechanics (for instance, a nanoparticle penetrating through a cell's membrane or a cell sucked with a pipette), the role of configurational forces is investigated during the process in which a compliant intruder is inserted into an elastic structure. For insertion into a rigid constraint, a configurational force proportional to the square of the strain needed to deform the body, which is penetrating, is found. This force has a more complex structure when the compliance of the constraint is kept into account, but in all cases, it tends to expel the penetrating body.