Streaming potential in the hydrodynamic entrance region of cylindrical and rectangular capillaries

摘要: Previous analyses of streaming potential in capillaries have ignored the region flow development that occurs near entrance all ducts. A new theory is presented which accounts for influence hydrodynamic on measurements under conditions where capillary dimensions are large relative to double-layer thickness. First, a general formulated having an arbitrary cross-sectional shape. Specific application then made two ducts most common experimental use; namely, cylindrical and rectangular capillaries. The results given terms correction factors modifying classical Helmholtz-Smoluchowski equation applies when sufficiently long.