In a previous paper, 1 we proposed an optofluidic modulator based on peristaltic flow. A microchannel made of polydimethylsiloxane is filled with nematic liquid crystal molecules that align homeotropically in the steady state. Once we apply a periodic peristaltic flow through mechanical deformation of the channel, liquid crystal molecules tend to realign with the gradient velocity field and thus change their optical properties. In this paper, we focus on the channel deformation with the finite elements program Comsol (R), and we highlight the limitations in frequency of such optofluidic components.