淤泥质港口航道适航密度确定方法的改进

Improvement of method for determining nautical density in muddy harbor

根据浮泥层中船舶航行时船体边壁带动附近浮泥作剪切流动的物理过程与浮泥在缓坡上的重力流之间的相似性,提出以船体边壁附近浮泥层流态转换条件来定义适航密度,以避免现行方法的不确定性,并提出了相应的计算方法。计算表明,适航密度与航行速度和浮泥层厚度有关。在通常航速和0.5～1.5 m浮泥层厚度条件下连云港航道的适航密度约为1.25～1.35 g/cm3。

A new approach for defining the nautical density using the flow pattern critical conditions of fluid mud around the walls of the ships is proposed based on the similarity between the form of shear flow as ships sail in the fluid mud layer and the gravity flow of fluid mud on the gentle slope. The new methodology can avoid the uncertainty of current ones. Relevant calculation method is provided. It is shown that the nautical density is related to the cruise speed and the thickness of the fluid mud layer. Under the general cruise speed and 0.5-1.5 m thick layer condition, the nautical density in the channel of the Lianyun port is about 1.25-1.35 g/cm3.