Sommaire:

Acoustic or blast wave absorption by liquid foams is especially efficient and bubble size or liquid fraction optimization is an important challenge in this context. A resonant behaviour of foams has recently been observed in linear acoustics, but the main local dissipative process is still unknown. We address this issue by measuring the pressure attenuation of a weak shock wave in a liquid foam, in the linear and weakly non-linear regimes. I will show that the pressure attenuation depends on the nature of the gas composing the foam and that a maximum of attenuation is obtained for a given bubble size. Those results are interpreted with a thermal dissipation model, featuring an optimal attenuating bubble size close to the thermal boundary layer. If I have time, I will also present some results on the foam rupture after the impact of the blast wave.

Pour plus d'informations, merci de contacter Truzzolillo D.