【作者】 庄亚平；

【导师】 张志俭；

【作者基本信息】 哈尔滨工程大学 ， 核能科学与工程， 2005， 硕士

【摘要】 本文对波形板汽水分离器板壁上的水膜流动进行了研究。从流体力学的基本原理出发,通过合理的简化、假设,把复杂的汽水分离过程简化为理想的汽水分离过程。取板壁上水膜的微元体进行分析,建立水膜无波动情况下的水膜流动的连续性方程、动量方程组,给出水膜入口、出口条件和板壁边界条件。采用控制容积法对控制方程组进行离散,对流项采用迎风差分格式,扩散项、连续方程采用中心差分格式。离散方程组采用高斯—赛德尔迭代和持续亚松驰相结合的方法计算,得到板壁水膜的厚度和速度分布。计算结果显示,水膜主要向下流动,汽流流动方向上,水膜厚度和速度在入口处迅速增加,之后在把部分位置厚度和速度不变化;在重力方向水膜厚度和速度一直增加,但增加的速度减小。 建立水膜波动流动的控制方程组,对水膜自由表面任意一点分别进行法向、切向进行受力分析,得到水膜表面动力学边界条件,结合水膜表面运动学边界条件,给出水膜表面的边界条件。以水膜的平均厚度和平均速度的比值为特征值,对控制方程和边界条件简化。假设一扰动源为水膜的入口条件,利用VOF方法对水膜表面的运动进行追踪,模拟水膜自由表面的形状。计算结果显示,水膜在板中部的波动剧烈,水膜表面变形严重,水膜波动的频率对水膜波动的情况有重要影响作用。在一定程度上,本文对波形板汽水分离器二次携带的产生及破膜速度的研究方法有参考价值。更多还原

【Abstract】 In this dissertation , water film flowing on walls of corrugated-plate moisture separator is studied . From the basic law of fluid mechanics , by reasonable simplifying and hypothesis , complicated moisture separating process is simplified as ideal process . Infinitesimal body of wall’s water film is analyzed , no wave water film flowing continuity equation and momentum equation are received , inlet ,outlet and wall condition are added as boundary condition . Equations are differenced by control volume algorithm , convection term is differenced by up wind difference algorithm , diffusion term and continuity equation are differenced by central difference algorithm . Differenced equations are solve by gauss-seidel and SUR method , profiles of water film thickness and velocity are gotten . The results shows that the film mainly flow down .Water film wave model is made on basis of N-S equation . Arbitrary point of water surface is analyzed , dynamics condition and kinemics condition are added as boundary condition . The ratio of water film average thickness and velocity is taken as characteristic quantity to simplify equations and boundary condition . A turbulence fountain is give as inlet. VOF method is used to track simulating water surface . Simulation results shows that water film fluctuate and wave deformation acutenes . Turbulence frequency has significant effect to water film wave . When frequency is low , wave crest is higher , on the contrast ,wave crest is low . To some extent , the way in this dissertation will be useful to study separator’s secondary droplets and critical velocity of corrugated-plate moisture separator .更多还原