摘要
为了解决传统光滑粒子动力学(SPH)方法求解三维变系数瞬态热传导方程时出现的精度低、稳定性差和计算效率低的问题,本文首先基于Taylor展开思想拓展一阶对称SPH方法到三维热传导问题的模拟,其次引入稳定化处理的迎风思想,最后基于相邻粒子标记和MPI并行技术,结合边界处理方法得到一种能够准确、高效地求解三维变系数瞬态热传导问题的修正并行SPH方法.通过对带有Direclet和Newmann边界条件的常/变系数三维热传导方程进行模拟,并与解析解进行对比,对提出的方法的精度、收敛性及计算效率进行了分析;随后,运用提出的修正并行SPH方法对三维功能梯度材料中温度变化进行了模拟预测,并与其他数值结果做对比,准确地展现了功能梯度材料中温度变化过程.
In this work, an improved parallel SPH method is proposed to accurately solve the three-dimensional（3D） transient heat conduction equation with variable coefficients. The improvements are described as follows. Firstly, the firstorder symmetric smoothed particle hydrodynamics（SPH） method is extended to the simulating of the 3D problem based on Taylor expansion. Secondly, the concept of stabilized up-wind technique is introduced into the convection term. Thirdly, the MPI parallel technique based on the neighboring particle mark method is introduced into the above improved SPH method, and named the corrected parallel SPH method for 3D problems（CPSPH-3D）. Subsequently, the accuracy, convergence and the computational efficiency of the proposed CPSPH-3D method are tested by simulating the3 D transient heat conduction problems with constant/variable coefficient, and compared with the analytical solution.Meanwhile, the capacity of the proposed CPSPH-3D for solving the 3D heat conduction problems with the Dirichlet and Newmann boundaries is illustrated, in which the change of temperature with time under the complex cylindrical area is also considered. The numerical results show that： 1） the proposed CPSPH-3D method has the better stability, higher accuracy and computational efficiency than the conventional SPH method no matter whether the particle distribution is uniform; 2） the calculating time can be well reduced by increasing the number of CPUs when the particle number is refined in the simulations of CPSPH-3D. Finally, the temperature variation in the 3D functionally gradient material is predicted by the corrected parallel SPH method, and compared with the other numerical results. The process of temperature variation in the functionally gradient material can be shown accurately.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2017年第13期1-12,共12页
Acta Physica Sinica
基金
国土资源部公益性项目(批准号:201411007-01)资助的课题~~
关键词
三维瞬态热传导
光滑粒子动力学
并行
功能梯度材料
3D transient heat conduction
SPH method
parallel
functionally gradient materials
