Fluctuation theorem for entropy production during effusion of an ideal   gas with momentum transfer
  We derive an exact expression for entropy production during effusion of an ideal gas driven by momentum transfer in addition to energy and particle flux. Following the treatment in Phys. Rev. E Vol. 74, 021117 (2006), we construct a master equation formulation of the process and explicitly verify the thermodynamic fluctuation theorem, thereby directly exhibiting its extended applicability to particle flows and hence to hydrodynamic systems. 
Kevin Wood, C. Van den Broeck, R. Kawai, and Katja Lindenberg