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本文研究了进行阴极保护的钢圆柱体的周围的电流密度分布。水流垂直于圆柱体轴,水速为0.17～4.0米/秒。在3.5% NaCl 溶液中,沿裸露圆柱体的电流密度的分布取决于电解液的流动而引起的扩散边界层的变化,这种电流密度的分布被定义为在不形成氧化膜的电解液中的标准分布。在具有含钙沉淀物(在人造海水中经一周的恒电流极化后形成)的圆柱体上的电流密度分布不同于标准分布而取决于形成沉淀物的条件。在薄氧化膜上的电流密度分布和标准分布情况相似,但是电流密度更低些。含钙沉淀物的组成受电解液流动形式的影响。在具有厚氧化膜和(或)锈层的圆柱体上的电流密度分布与标准分布有很大差别。在具有锈层和含钙层的表面上在一定的条件下可具有最低的平均电流密度,但在高速水流下,由于氧化膜脱落就会导致局部很高的电流密度。
This paper investigates the current density distribution around the cathodic protection steel cylinder. Flow perpendicular to the cylinder axis, the water velocity of 0.17 ~ 4.0 m / sec. In a 3.5% NaCl solution, the distribution of the current density along the exposed cylinder depends on the change of the diffusion boundary layer caused by the flow of the electrolyte, which is defined as the difference between Standard distribution. The current density distribution on a cylinder with a calcium-containing precipitate (formed after a week of constant current polarization in artificial seawater) differs from the standard distribution depending on the conditions under which the precipitate is formed. The current density distribution on the thin oxide film is similar to the standard distribution, but the current density is lower. The composition of calcium-containing precipitates is influenced by the flow pattern of the electrolyte. The current density distribution on cylinders with thick oxide and / or rust layers is quite different from the standard distribution. The surface with the rust layer and the calcium layer may have the lowest average current density under certain conditions, but at high speed the flow will result in a locally high current density due to the oxide film falling off.