【摘要】 为了分析浮式液化天然气平台薄膜式储罐底部斜坡对流体晃动的影响规律,建立了仿真模型用于描述晃动储罐内的流体行为.流体自由液面运动通过流体体积法和k-ε湍流模型进行模拟,利用文献中的实验数据和仿真结果对该模拟的准确性进行验证.为了研究底部斜坡对流体晃动的影响,对不同斜坡尺寸、填充率以及储罐低阶固有频率下的流体晃动过程进行了仿真模拟.结果显示,固有频率可由水力参数的平均峰值决定,固有频率和储罐壁面压力载荷随着斜坡尺寸的增大而减小,当斜坡占比从5%增加到20%,壁面峰值压力下降了5.45 kPa.但该壁面峰值压力的变化只在填充率较低时明显,当填充率较高,如60%时,流体运动特性稳定,受斜坡结构改变的影响很小.流体仿真建模与分析结果对薄膜式液化天然气储罐的优化设计和运行提供了数据支撑.更多还原

【Abstract】 To analyze the bottom slope’s effect on the sloshing liquid in floating liquefied natural gas(FLNG) membrane tanks, a simulation model is built and applied to describe the liquid behavior in a sloshing container. The free surface motion is simulated by the volume-of-fluid method and the standard k-ε turbulence model. Experimental data and numerical results from references are used to validate the accuracy of the proposed simulation model. To study the influence of the sloped bottom on the liquid sloshing, different slope sizes and filling ratios are numerically simulated at the lowest natural frequency. The results reveal that the natural frequency can be determined by the average peak values of hydrodynamic parameters. The natural frequency and pressure loading on the tank walls decrease with the increase in the slope size. The peak pressure on the wall decreases by 5.45 kPa with the increase in the slope ratio from 5% to 20%. However, the relationship between the peak pressure and slope ratio is more significant with lower filling rates. Liquid behavior is more stable and independent with the change of the slope structure at a high filling rate(60%). The results of numerical simulation and modeling are expected to provide reference data for the design and operation of the FLNG system.更多还原