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arXiv · 2205.03127

Delayed elastic contributions to the viscoelastic response of foams

François A. Lavergne·Peter Sollich·Véronique Trappe
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Abstract

We show that the slow viscoelastic response of a foam is that of a power-law fluid with a terminal relaxation. Investigations of the foam mechanics in creep and recovery tests reveal that the power-law contribution is fully reversible, indicative of a delayed elastic response. We demonstrate how this contribution fully accounts for the non-Maxwellian features observed in all tests, probing the linear mechanical response function. The associated power-law spectrum is consistent with soft glassy rheology of systems with mechanical noise temperatures just above the glass transition [Fielding et al., J.Rheol. 44, 323(2000)] and originates from a combination of superdiffusive bubble dynamics and stress diffusion, as recently evidenced in simulations of coarsening foam [Hwang et al., Nat.Mater. 15, 1031 (2016)].

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François A. Lavergne, Peter Sollich, Véronique Trappe. 2022-05-06. Delayed elastic contributions to the viscoelastic response of foams. https://doi.org/10.1063/5.0085773

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