On bipolar space-charge structures in low conductive liquids in an external electrostatic field

The general set of equations for the case of electrostatic field in a low conductive liquid in the interelectrode gap of a plane-parallel capacitor is formulated. The basic equation for the distribution of the electric field strength is obtained, and similarity criteria for the processes of current transport and charge formation are found. The conditions that define the form of the field distribution are established by analysis of signs of the first and second derivatives of the electric field strength. In particular, it is shown that formation of bipolar structures is impossible in the case of "pure" polarization when current equals zero. Alternatively, their formation is linked with the passage of a sufficiently strong current. Ways to solve the basic equation are developed. The approximate solution for the general case of the problem is given.