Flow Characteristics and Its Friction Coefficient of Laminar Near-Wall Boundary Layer in Dusty Atmosphere

采用双向耦合的双流体模型,研究了大气悬浮沙尘的存在对大气边界层中层流底层流动特性及摩阻系数的影响,计算并讨论了不同沙尘含量下含尘大气相对于无尘大气摩阻系数的变化。结果表明：摩阻系数的变化取决于悬浮沙尘的初始运动状态和质量载荷率。

Serrated Plastic Flow in a Zr-Based Bulk Metallic Glass During Nanoindentation

We investigate plastic deformation of Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass using depth sensing nanoindentation. Numerous serrations in the load-displacement curves during indentation, shear bands and pile-ups around the indent were observed. The results revealed that the serrated plastic flow behaviour in this alloy depends strongly on the indentation strain rate.

Characterization of Air-Water Two-Phase Vertical Flow by Using Electrical Resistance Imaging

The characterization of air-water two-phase vertical flow in a 12 m flow loop with 1.5 m of vertical section is studied by using electrical resistance tomography (ERT). By applying a fast data collection to a dual-plane ERT sensor and an iterative image reconstruction algorithm, relevant information is gathered for implementation of flow characteristics, particularly for flow regime recognition. A cross-correlation method is also used to interpret the velocity distribution of the gas phase on the cross section. The paper demonstrates that ERT can now be deployed routinely for velocity measurements and this capability will increase as faster measurement systems evolve.

不同热化学非平衡模型对高超声速喷管流场影响的数值分析

采用轴对称NS方程，数值研究不同热化学非平衡模型对高超声速喷管流场的影响，包括：（1）不同组元数的高温空气模型（5组元、7组元、11组元）的比较；（2）热力非平衡（双温度）的化学动力过程与热力平衡（单温度）的化学动力过程的比较。计算结果表明，高焓风洞实验条件下喷管流场处于热力和化学都是非平衡的状态。在计算条件下，数值模拟以采用7组元或11组元的热化学非平衡模型为宜。