Dynamic response of open cell dry foams
  We study the mechanical response of an open cell dry foam subjected to periodic forcing using experiments and theory. Using the measurements of the static and dynamic stress-strain relationship, we derive an over-damped model of the foam, as a set of infinitesimal non-linear springs, where the damping term depends on the local foam strain. We then analyse the properties of the foam when subjected to large amplitudes periodic stresses and determine the conditions for which the foam becomes optimally absorbing. 
Buddhapriya Chakrabarti, Peter J. Hine, and B. M. A. G. Piette
cond-mat.soft