压载水旋流预处理单元的优化设计与数值模拟

压载水管理公约 D2对压载水中颗粒物粒径范围及含量做出了明确规定。为满足此规定，水力旋流器逐步开始应用于船舶压载水处理系统中。为了提高水力旋流器的分离效率，通过改变水力旋流器的入口结构对水力旋流器进行优化，即将入口结构设计为阿基米德螺线形入口来增加流体转动速度，降低能量消耗，从而提高分离效率。应用 Fluent软件，结合雷诺应力模型（RSM）和混合多相流（Mixture）分析方法，对优化前、后的水力旋流器进行固-液两相流数值模拟。模拟内容包括水力旋流器内的速度分布、固相体积分数分布以及分离效率等。通过对比2种模型的模拟结果，说明优化的水力旋流器内部的流场速度以及分离效率均有一定的提高，达到了优化目的。

Optimal design and numerical simulation of cyclone pretreatment unit in ballast water system

The ballast water management standard D2 established by IMO has made clear rules for the range of particles size and content in the ballast water. In order to meet the rules, the hydrocyclone has begun to be widely applied in treatment of ship’s ballast water. However, in order to improve the separation property of the hydrocyclone, optimize the hydrocyclone by changing its entry structure. The cyclone entry structure is designed as Archimedes spiral entrance to increase fluid rotational speed, reduce the energy consumption and finally improve the separation efficiency. Using Fluent software and combining with the Reynolds stress model and the mixture multiphase model to simulate the solid-liquid multiphase of the two structures of Archimedes entrance and tangential entrance hydrocyclone. The simulation includes the fluid field distribution and solid volume fraction distribution inside the hydrocyclone and the separation efficiency. The simulation results show that: compare to the tangential entrance, the tangential velocity and separation efficiency both increased, achieved the goal of optimization.