基于虚拟载荷谱的车身疲劳预测研究

分别对VPG提载技术以及CAE疲劳预测方法进行了介绍,以实际开裂问题为例,对开裂现象进行了原因分析,并利用CAE技术对失效问题进行复盘,最后对其进行优化改进。实践证明,基于虚拟载荷谱的整车疲劳预测方法,在新车型开发过程中可以准确预测整车疲劳薄弱区域,减少试验轮次、节约成本、缩短开发周期,在新车型开发过程中起到非常重要的作用。

NUMERICAL STUDY OF THE RELATIONSHIP BETWEEN APPARENT SLIP LENGTH AND CONTACT ANGLE BY LATTICE BOLTZMANN METHOD

The apparent slip between solid wall and liquid is studied by using the Lattice Boltzmann Method （LBM） and the Shan-Chen multiphase model in this paper. With a no-slip bounce-back scheme applied to the interface, flow regimes under different wall wettabilities are investigated. Because of the wall wettability, liquid apparent slip is observed. Slip lengths for different wall wettabilities are found to collapse nearly onto a single curve as a function of the static contact angle, and thereby a relationship between apparent slip length and contact angle is suggested. Our results also show that the wall wettability leads to the formation of a low-density layer between solid wall and liquid, which produced apparent slip in the micro-scale.

预处理软化+膜工艺深度处理阴极铜废水

某铜业公司阴极铜生产废水为3 000 m3/d,主要包括酸性废水中和后出水、化学水处理站浓水和普通生产废水。深度处理系统根据生产需要,处理酸性废水、化学水站浓水、普通生产废水单股或多股混合废水。由于深度处理项目建设与铜业公司建设同步,设计阶段对来水水质只能根据矿石组成和同类型废水水质进行估算,其中总硬度≤800 mg/L、总碱度≤600 mg/L、SS≤200 mg/L、硫酸盐≤900 mg/L。通过Mathematica软件模拟计算和可能的来水水质进行分析验证,深度处理系统采用多阶混凝沉淀+多介质过滤+离子交换+膜系统工艺,处理后80%清水达标进入厂区回用水管道,其余浓水进入渣缓冷循环水管道。该项目建成运行后,深度处理系统脱盐率≥97%,出水水质达到业主确定的软化水水质标准。