基于大涡模拟的波形板汽水分离器数值研究

采用Lagrange-Euler方法对波形板汽水分离器内离散气-液两相流动进行了数值模拟研究。对于连续相,使用大涡模拟(LES)湍流模型替代常见的雷诺平均模型(RANS)进行数值模拟。大涡模拟方法将湍流分为大、小两种尺度,大尺度涡采用直接数值求解,只对小尺度湍流脉动建立模型。此方法不仅可给出更准确的分离效率等整体性能,同时可得到流动的瞬态细节和湍流脉动对液滴的影响,进而获得更为准确可信的液滴轨迹。计算结果表明,大涡模拟得到的结果同实验结果符合良好;与雷诺平均模型相比,大涡模拟可为汽水分离器的机理研究和优化设计提供更基础的模型。

Numerical Study of Corrugated Plate Steam-water Separator Based on Large-eddy Simulation

Lagrange-Euler method was used to simulate the droplet-laden flow in corrugated plate separators.In order to calculate the turbulence of continuous phase,largeeddy simulation (LES) turbulence model was chosen to replace the Reynolds-averaged Navier-Stockes equations (RANS).The turbulence was divided into large scale and small scale in large-eddy simulation.The large scale vortexes were calculated directly,while small scale vortexes were modeled.This method not only can give more accurate overall performances,such like the separation efficiency,but also can show the details of transient turbulence flows.Therefore,more accurate and reliable trajectories of droplets can be obtained.The results obtained by large-eddy simulation are in good agreement with experiment results.Compared with results obtained by the RANS,largeeddy simulation can provide more informations on the mechanism of the corrugated plate separator which are important for optimal design of corrugated plate separators.