| 摘要 |
PURPOSE:To make the highly accurate measurement of frozen layer thickness possible with simple construction by so constituting the same that the stray electrostatic capacity generated in the insulated conductive part connected to an electrode bar is negligible. CONSTITUTION:The surface of a conductive bar 3 is covered with an insulation film 4 of high dielectric constant. The radius of the bar 3, the radius including the film 4, the radius of the core 5 of an insulated conductor 6 connected to the bar 3, the radius of the conductor 6, and the dielectric constants of the insulation films and insulators of the bar 3 and the conductor 6 are selected at prescribed values. Thereby, the electrostatic capacity formed between an electrode bar 2, the conductor 6 and water 10 to be cooled is hardly affected by the fluctuating values in the stray capacity, and the accuracy of measurement is improved. |
