Abstract: Particles such as fish excretion and residual feed are easy to deposit in the pipeline and cause blockage, thus affecting the cleaning of water in aquaculture tank and causing adverse effects on fish.  Based on the numerical simulation of Lagrangian two-phase flow, the flow characteristics of particles in drainage piping are simulated, the suitable turbulence model and calculation scheme are calibrated based on the slurry pump pipe lifting test results, and the analysis and research are carried out accordingly. The flow characteristics of particles under different particle size, flow velocity and pipe diameter are analyzed. The results show that the SST K - ω turbulence model has high accuracy for the particle flow in the drainage piping. The influence of particle size on flow is very obvious. When the particles are small enough, the turbulence, drag and saffman force play a dominant role. When the particles reach a certain size, gravity becomes the main factor. For particle deposition, the influence of particle size is the largest, followed by inlet velocity, and the influence of pipe diameter is the least.

Key words: drainage piping, particles., flow characteristics, aquaculture ship

摘要： 鱼类的排泄及残饲等颗粒物易在管路中沉积造成堵塞，从而影响养殖水舱内水体清洁，并对鱼类产生不利影响。基于拉格朗日两相流数值模拟技术对排水管路内颗粒物流动特性进行仿真，通过矿浆泵管路提升试验结果标定了合适的湍流模型及计算方案，并据此开展分析研究。重点分析了颗粒物在不同粒径、不同进水流速、不同管径下的流动特性。结果显示：针对排水管路内的颗粒物流动问题，SST k-ω湍流模型具有较高的准确性；颗粒大小对流动影响非常明显，当颗粒足够小时，流体湍动、曳引、萨夫曼力等影响占据主导作用，而当颗粒达到一定大小后，重力则成为主要影响因素；就沉积情况而言，颗粒粒径影响最大，管路进口流速次之，管径的影响最小。

关键词: 排水管路, 颗粒物, 流动特性, 养殖工船