Trial manufacture of a fluid-type static induction transistor

It is well known that streaming electrification occurs when a liquid with good insulating properties is made to flow through a pipe. This is called “streaming current”, and its magnitude relates to such factors as the length and diameter of the pipe, and the flow velocity and conductivity of the liquid. The best known description of this electrification phenomenon is Klinkenberg´s Electrostatics in the Petroleum Industry (1958). This work reports experiments in which variations in types of liquids and pipe materials, flow length and velocity, and use of interface activation additives were introduced in order to analyse the properties of the current. Subsequently, further experiments of the same kind were performed by Bustin, Koszman and others. However, the fact that virtually identical research is still being carried on today suggests that very little new progress is taking place. In order to achieve new findings, we need to adopt a new stance and take a fresh look at the whole phenomenon. Streaming electrification occurs when a liquid is forced to flow through a capillary tube under pressure ΔP. In these circumstances, a voltage difference V is generated between a pair of electrodes. ΔP and V relate to one another through the viscosity η, the conductivity κ, and the relative permittivity ε of the liquid, and through the ξ potential between the liquid and the tube. By making use of these relations, it is possible for pressure ΔP to be replaced in calculations by potential difference It is in this conceptual framework that the present paper discusses the streaming electrification phenomenon by means of a method based on semiconductor theory