摘要
采用无网格格子-玻尔兹曼法（LBM）模拟计算错流换热器流体力学,并与CFD模型对比.结果表明,结合大涡模拟（LES）,LBM合理预测了错流换热器湍流流体力学,模拟速度分布与文献结果吻合较好,关键物理量计算误差均在工程允许范围内.LBM与CFD模型模拟结果大致相同,计算时间相近,计算效率无明显差异.CFD模型需大量前处理时间用于网格划分,尤其对于具有复杂几何内构件的换热器,网格处理更复杂.LBM基于粒子追踪计算平衡态分布函数的演化,采用格子概念替代原网格,只需指定格子离散尺寸,无需适应几何边界的空间离散,模型适用性更强,建模过程更高效,适合复杂几何结构的模拟.
A meshless approach based on the LBM（Lattice-Boltzmann Method） was employed for simulating a cross-flow heat exchanger. The calculated hydrodynamics was compared with the CFD for discussion. The results showed that the LBM combined with LES predicted the turbulent hydrodynamics of the heat exchanger reasonably. The simulated fluid velocity distributions agreed with the referenced experimental data. The calculation deviations on key physical quantities were also acceptable for engineering purpose. The subsequent comparison indicated that the LBM and CFD had almost the same calculation results and cost. There was no apparent difference in the computational efficiency between the two models. Nevertheless, the CFD simulation required more effort in the pre-process for mesh generation. This problem was especially serious for simulating the heat exchangers with complex internals. In contrast, the LBM was a particle based method. It predicted the hydrodynamics by tracking the probability distribution function to an equilibrium state. The concept of discrete grids was replaced by the lattice. It only needed to specify the lattice size regardless of the geometrical adaption. Hence, the LBM modeling was considered to be more efficient and it was suggested highly for the simulation design of complex geometrical structures.
出处
《过程工程学报》
CAS
CSCD
北大核心
2018年第1期35-40,共6页
The Chinese Journal of Process Engineering
基金
国家自然科学基金资助项目(编号:21176082)
国家高技术研究发展计划(863)基金资助项目(编号:2011AA06A102)
关键词
错流列管
湍流
格子-玻尔兹曼法
计算流体力学
模拟效率
cross-flow tube bundle
turbulence
Lattice-Boltzmann method
computational fluid dynamics
simulation efficiency
