Chunju WANG
,
Debin SHAN
,
Bin GUO
,
Jian ZHOU
,
Lining SUN
材料科学技术（英）
From the viewpoint of production engineering, microforming is considered as an effective process to fabricate various microparts. Several key problems in microforming processes were investigated. A new microforming apparatus with a high stiffness piezoelectric actuator as the punch driver was developed to produce microparts. To improve the forming abilities and locate the billets, a floating microdie was designed. The size effects of the billets and die cavities on the microforming abilities were studied with upsetting and coining tests, respectively. And the isothermal microforming process of microgears was performed with the developed microforming apparatus. Several analysis methods were used to evaluate the forming quality of the microparts.
关键词:
Microforming
,
尺寸效应
,
微塑性成形设备
,
浮动
高诚
,
胥蕊娜
,
陈黎
,
姜培学
工程热物理学报
格子Boltzmann方法(LBM)在计算复杂结构物理模型时具有独特优势并在模拟两相流动过程中能够高效清晰捕捉相界面.本文介绍了基于Shan-Chen多相模型的格子Boltzmann方法的理论成果以及基于二氧化碳封存的超临界两相流的模拟研究.结果表明,Shan-Chen模型在模拟两相流时符合Laplace定律,且两相层流时的速度分布和相渗曲线均与理论值吻合.二氧化碳封存过程中,较大的注入速率在提高二氧化碳残余俘获量的同时会降低其化学俘获量.
关键词:
二氧化碳封存
,
超临界两相流
,
Shan-Chen模型
黄桥高
,
潘光
功能材料
doi:10.3969/j.issn.1001-9731.2015.10.005
润湿性对固体表面上液体的各种动力学行为具有重要影响，疏水表面的特殊润湿性是其在减阻、降噪、防污等领域有着广泛应用前景的根本原因。基于Shan-Chen模型的格子Boltzmann方法对疏水表面润湿性进行数值模拟，获得了材料属性和微形貌对疏水表面润湿性的影响规律。研究表明，要使疏水表面处于 Cassie-Baxter 润湿状态，微形貌高度必须大于某一临界值，而当疏水表面一旦处于 Cassie-Baxter 润湿状态后，继续增加微形貌高度也不会提高其疏水性能；疏水表面的表观接触角随气液界面分数先增大后减小，且存在一个最佳的气液界面分数使表观接触角达到最大。
关键词:
疏水表面
,
格子Boltzmann方法
,
材料属性
,
微形貌
,
润湿性
