The hydrodynamic aspects of functioning of a high-voltage infiltration nanogenerator employing the potential energy of a liquid entering a glass filter are considered. This energy transforms into electric energy due to the formation of a double electric layer owing to the triboeleсtrification effect during the infiltration of the dielectric liquid through the porous structure. To solve the emerged problems, two local effective parameters were introduced in the equations of a hydrodynamic flow along the infiltration path: mechanic density and dynamic viscosity. The working equations for the motion of the liquid were derived; the solutions for the velocity and the flow rate that determine the electric characteristics of a nano-generator—the electric charge and potential as well as their physical relationships—were obtained.