  We study the current rectification of particles moving in a pulsating channel
under the in uence of an applied force. We have shown the existence of diferent
rectification scenarios in which entropic and energetic effects compete. The
effect can be quantified by means of a rectification coefficient that is
analyzed in terms of the force, the frequency and the diffusion coefficient.
The energetic cost of the motion of the particles expressed in terms of the
entropy production depends on the importance of the entropic contribution to
the total force. Rectification is more important at low values of the applied
force when entropic effects become dominant. In this regime, the entropy
production is not invariant under reversal of the applied force. The phenomenon
observed could be used to optimize transport in microfluidic devices or in
biological channels.
