储罐内流体边界层填充多孔材料后的流动分析

摘要

现有文献关于液化天然气(LNG)储罐内填充多孔材料的研究相对较少.为此,通过Fluent 6.3建立了多孔介质中湍流流动的二维模型,多孔材料采取边界层填充以及不同的填充厚度,对储罐内液化天然气的流动情况进行数值模拟,并与无多孔材料填充时液化天然气流动情况进行对比.研究结果表明:在储罐边界层内填充多孔材料可使罐体两边的流动强度较弱,中间的流动强度较强,两侧滚动圈的滞留区面积比中间滚动圈大,同时可减弱流动强度,延迟压力出口有质量流出的时间,减少液体蒸发量,减少下层液体积聚的能量,因此可在一定程度上抑制翻滚的发生.研究结果可为储罐内填充多孔材料抑制LNG翻滚事故的发生提供理论指导.%Few literatures have reported on the filling of porous materials in LNG storage tanks.In view of this,a two-dimensional model of turbulent flow in porous media is established using Fluent 6.3.In the model,the boundary layers are filled with porous material with different filling thicknesses.Numerical simulation of the LNG flow in porous material filled storage tank is carried out,and is compared with that in storage tank without porous materials.The results show that filling the porous material in the boundary layer of the tank can lower the flow intensity on both sides of the tank.The middle flow intensity remains strong.The stagnant area of the rolling circle on both sides is larger than that of the middle rolling circle,resulting in reduced flow intensity,delayed the mass outflow time at the pressure outlet,reduced amount of liquid evaporation and accumulation energy of lower liquid.Therefore,it can suppress the occurrence of rolling to a certain extent.The study can provide theoretical guidance for the researches on suppressing the occurrence of LNG rolling by porous material filling in storage tank.