基于计算流体力学模型的旋流分离器的优化设计

Optimization of Cyclone Vapor-liquid Separator with CFD Simulation

气液旋流分离器已应用于多个行业,但在制冷领域中的研究则相对较少。通过数值模拟及实验的方法,考察了气液旋流分离器在制冷系统中的分离效果并且提出减小分离器体积的优化方法。建立制冷剂两相流气液旋流分离器模型,利用CFD软件FLUENT对其进行数值模拟,其中离散相采用DPM模型,湍流模型采用RNG k-ε模型,得到了分离器内部速度场、液体相浓度分布以及不同颗粒直径下的进出口干度。采用计算焓值的方法对旋流分离器进行了实验研究,通过实验方法得出旋流分离器拥有良好的分离效果,在进口干度为0.3时,出口干度达0.97以上并且对比数值模拟及实验推导得到液相颗粒直径约为1×10-6米量级。在此基础上对分离器结构进行优化,通过改变折流板圈数,在使分离器出口干度没有明显变化的前提下,体积缩小了约31%。

The effect of the separation and the optimization of the separator in refrigeration systems were examined via simulation and experiment.A model of flow and heat transfer in a cyclone vapor-liquid separator was established.The CFD simulation for the separator was performed by the FLUENT with the DPM model and the RNG k-ε model.The distributions of velocity and the concentration of liquid phase,and the outlet quality and the inlet quality at different liquid droplet diameters were gained.The experimental results show that the cyclone separator used in the refrigeration system had a good separation effect,leading to the outlet quality of 0.97 when the inlet quality was 0.3.The diameter of the liquid droplets was about 1×10-6m derived by the comparison between the simulation results and the experimental data.In addition,the separator size was reduced by about 31% without obvious change in the outlet quality by increasing the circles of the baffle board.