基于LBM的多孔介质/流体交界面滑移效应细观研究

• 作 者: 蔡鹏飞 陈宝明 张国庆 刘芳 张星 云和明
• 机 构: 山东建筑大学热能工程学院,济南,250101;山东建筑大学热能工程学院,济南250101;可再生能源建筑利用技术省部共建教育部重点实验室,济南250101;山东省可再生能源建筑应用技术重点实验室,济南
• 出 处: 工程热物理学报
• 发表日期: 2016年2期
• 关键词: cavity partially filled with actual porous media lattice Boltzmann method slip e

本文采用格子Boltzmann方法对真实多孔介质复合腔体内的自然对流进行了研究,分析了在不同瑞利数Ra、多孔介质厚度6和高度Y条件下交界面处的滑移效应的变化规律.利用X-CT技术对真实多孔介质材料进行断层扫描,通过Matlab对图片进行处理并导入格子Boltzmann模型中进行求解.计算结果表明:当0.1＜Y＜0.9,复合腔体交界面速度滑移系数α和应力跳跃系数β随高度Y基本保持不变,而在靠近上下壁面时(Y＜0.1和Y＞0.9)变化明显;在一定的高度处,α和β均随Ra数发生缓慢变化;多孔介质的厚度δ对α和β影响较小.“,”The model on natural convection in a cavity partially filled with an actual porous layer was studied and solved numerically by lattice Boltzmann method.The slip effect at the porous/fluid interface was analyzed under different Ra number,height and thickness of the porous medium conditions.The images of real porous structure obtained by X-ray computed tomography technique and processed by Matlab were imported into the lattice Boltzmann model for solving.The numerical results showed that the velocity slip α and stress jump coefficient β would be almost constant with different height (0.1 ＜ Y ＜ 0.9),but they will change significantly (Y ＜ 0.1 and Y ＞ 0.9);at a certain height,α and β will reduce gradually with increasing Ra number,but variation with thickness is not obvious.