Development of charge in low conductivity liquids flowing past surfaces: A theory of the phenomenon in tubes

Abstract The phenomenon of charge generation in low conductivity liquids as they flow past surfaces is described. A brief review and critique of theories previously proposed to explain the observations is given. A new, general formulation which may be particularized to specific situations is developed for the phenomenon in tubes. The equations developed are solved for the special case of uniform velocity profile and the solution is compared with previous theories. It is shown to be the same as the solution for very low conductivity and agrees in form with reported experimental observations. Several predictions are able to be made for higher conductivities from the equations, and these are shown to agree with observation.