A boundary-layer momentum integral equation is solved by using Pohlhousen's biquadratic expression for velocity distribution in order to clarify laminar boundary layers in the entrance region between parallel plane electrodes. The positions, in which two laminar boundary layers come together to cause the potential core to vanish, and in which they transit from laminar to turbulent, are obtained and shown in Fig. 5.
It is concluded through the experiments, in which workpieces of pure iron are electrochemically machined with sodium nitrate solution, that the change of the cathode shape due to the deposition of anodic products is inverted onto the anode surface to deteriorate the accuracy. Hydrodynamic conditions are presented to prevent the deposition in terms of the results of the analysis for the laminar boundary layers.