How fast do fluids squeeze through microscopic single-file pores?

A one dimensional symmetric exclusion model is used to study pressure and osmosis driven flows through molecular-sized channels, such as biological membrane channels and zeolite pores. Analytic expressions are found for the steady-state flow as a function of pore radius, pore energetics, reservoir temperature, driving force, and internal defects. We find a flux maximum as a function of particle-pore interactions: This, and other nonlinear dependences suggest numerous diagnostic experiments for biological and zeolitic systems.