论文标题
单个放松时间和多个经过修订的矩阵晶格玻尔兹曼模拟了强迫各向同性湍流
Single Relaxation Time and Multiple Revised Matrix Lattice Boltzmann Simulations of Forced Isotropic Turbulence
论文作者
论文摘要
比较了三维强迫各向同性湍流的模拟，分别分辨率为128^3和256^3，比较了单个松弛时间（SRT）和修订后的矩阵（RM）晶格玻尔兹曼模型。 Guo等人的强迫技术。 （2002）使用相同的参数和条件将两个模型应用。已经确认了一些新的方面和结果，例如MRT模型的优越性，以模拟强迫性湍流并使用Courant-Friedichs-Lewy条件（CFL）（Courant等，1967）（Courant等，1967），通过将速度输入与系数CFL <1.0相乘，以越过稳定性问题，以越过稳定性问题并将输出Velocity数据划分为同一CFL。选择初始速度场作为U（X; 0）= 0，并在所有情况下以固定强迫幅度为10^-4的低波数注入力。在所有SRT模拟中，单个放松时间均设置为0.503。结果表明，所获得的湍流速度场在以前的理论，实验和数值研究中得到了普遍特征。模拟的泰勒·雷诺数（Taylor Reynolds）的数量分别为SRT：r = 62和MRT：1283和SRT：r = 107和MRT：R = 82的MRT：R = 65。为了测试与MRT模型相比，SRT模型的弱不可压缩性，描述了密度概率分布函数（PDF），发现是吗？对于MRT案例，几乎是所有时间步的统一性，而SRT案例对统一的明显干扰。
The single relaxation time (SRT) and the revised matrix (RM) lattice Boltzmann models are compared for simulations of three dimensional forced isotropic turbulence with resolutions of 128^3 and 256^3, respectively. The forcing technique by Guo et al. (2002) is applied with the two models using the same parameters and conditions. Some new aspects and results have been confirmed such as the superiority of the MRT model to simulate forced turbulence and using the Courant-Friedichs-Lewy condition (CFL) (Courant et al., 1967) by multiplying the velocity input with the coefficient CFL < 1.0 to overcome the stability problem and divide the output velocity data by the same CFL. The initial velocity field is chosen as u(x; 0) = 0 and the force is injected at low wave-numbers with a fixed forcing amplitude to 10^-4 for all cases. The single relaxation time is set to 0.503 in all SRT simulations. Results show that the obtained turbulent velocity fields yield universal characteristics as proven in previous theoretical, experimental and numerical studies. The Taylor Reynolds number for the simulations are found as SRT: R = 62 and MRT : R = 65 for 1283 and SRT: R= 107 and MRT: R = 82 for the case of 2563, respectively. To test the weak incompressibility for the SRT model in comparison to the MRT model, the density probability distribution function (PDF) is depicted and it is found that ? is almost unity at all timesteps for the MRT case, while a clear disturbance about unity is observed for the SRT case.
