Herschel-Bulkley流体的修正多松弛参数格子玻尔兹曼方法

• 作 者: 吴伟伟 黄筱调 袁鸿
• 机 构: 南京工业大学机械与动力工程学院,南京,211800
• 出 处: 工程热物理学报
• 发表日期: 2017年9期
• 关键词: Herschel-Bulkley fluids modified MRT LBM poiseuille flow cement-3D prnting MRT L

Herschel-Bulkley流体作为非牛顿流体中重要的一类,已广泛应用于工程领域.为了改善LBM对Herschel-Bulkley流体流动模拟时的稳定性和精度,在多松弛时间参数LBM(MRT LBM)的基础上提出了一种改进方法.以Poiseuille流为例,对改进算法进行了详细介绍,对剪切变稀型和剪切增稠型流体分别进行对比,并比较在不同指数情况下的相对误差随格子数增大的变化趋势,说明了此改进方法的有效性,最后通过在水泥3D打印喷头中的应用,与多松弛时间参数的LBM(MRT LBM)的模拟结果进行对比,进一步验证了此改进方法的可行性.“,”As an important kind of non-Newtonian fluids,Herschel-Bulkley fluids have been applied into engineering widely.When the lattice Boltzmann method (LBM) was used in Herschel-Bulkley flow,a modified method based on multiple-relaxation-time lattice Boltzmann method was presented to improve the stability and accuracy of the simulation.Then Poiseuille flow was taken as an example to discuss the detailed process of the modified method.Also the variation trends of the relative errors with the lattice nodes in case of different power-law indexes were analyzed.The results showed that the modified method was efficient.Finally,the method was applied into the flow in the extruder of cement-3D printing,and the numerical results were compared with that of multiple-relaxation-time lattice Boltzmann method (MRT LBM),which further proved the feasibility of the method.