  This work presents a combined numerical and experimental approach to
characterize the macroscopic transport and acoustic behavior of foam materials
with a membrane cellular structure. A direct link between the sound absorption
behavior of a membrane foam-based layer and its local microstructural
morphology is also investigated. To this regard, we first produce a set of foam
samples having the same density and the same monodisperse pore size but
different values of the closure rate of the windows separating the foam pores.
Then, the morphology of pore connectivity with membranes is measured directly
on SEM together binocular images. The obtained morphological information is
used to reconstruct the representative unit cell for computational performance.
The knowledge of the computational model of acoustic porous materials obtained
by a hybrid approach based on the scaling laws and the semi-phenomenological
JCAL model. For validation purpose, the numerical simulations are further
compared with the experimental data obtained from a set of three-microphone
tube tests, a very good agreement is observed. In acoustic terms, the obtained
results point out that for the given high porosity and cell size, we can
archive a high sound absorbing ability of based-foam layer by controlling the
membrane level at a range of 45-85$\%$. To elaborate these foams, a gelatin
concentration in a range of 14-18$\%$ should be used in the foam making
process. In addition, we can obtain for instance the peak and the average
values of acoustic absorption of a foam layer in a specific frequency range of
interest by varying its membrane content. Methodologically, our work proposes
(i) a systematic approach to characterize directly macroscopic properties from
the local microstructure, and (ii) a manufacturing technique that can be used
to make foams with the desired microstructure.
