Refaie Ali Ahmed, Abbasi Waqas Sarwar, Younus Rabia, Rahman Hamid, Nadeem Sumaira, Majeed Afraz Hussain, Ahmad Irshad
Department of Mathematics and Computer Science, Faculty of Science, Menoufia University, Shebin El Kom 32511, Menofia, Egypt.
Department of Mathematics, Air University, Islamabad, 44000, Pakistan.
Sci Rep. 2024 Jul 5;14(1):15524. doi: 10.1038/s41598-024-65423-4.
This study investigates the influence of small control cylinders on the fluid dynamics around a square cylinder using the Lattice Boltzmann Method (LBM). Varying the gaps (L) between the main and control cylinders from 0 to 6, four distinct flow regimes are identified: the solo body regime (SBR), shear layer reattachment (SLR), suppressed fully developed flow (SFDF), and intermittent shedding (IS). The presence of control cylinders results in significant reductions in flow-induced forces, with drag coefficient (CD) and root mean square values of drag and lift coefficients (CD and CL) decreasing by approximately 31%, 90%, and 81%, respectively. The SFDF flow regime exhibits the lowest fluid forces compared to other regimes. The effects of tiny control cylinders on the fluid flow characteristics of a square cylinder are examined using the Lattice Boltzmann Method (LBM) in this research work. The gaps (L) between the main and control cylinders are varied in the range from 0 to 6. The size of each control cylinder is equal to one-fifth of the primary cylinder. According to the findings, there are four distinct flow regimes as the gap spacing varies: solo body regime (SBR), shear layer reattachment (SLR), suppressed fully developed flow (SFDF), and intermittent shedding (IS) for gap spacing ranges 0 ≤ L ≤ 0.2, 0.3 ≤ L ≤ 0.9, 1 ≤ L ≤ 3, and 3.2 ≤ L ≤ 6, respectively. Additionally, it has been noted that the amplitude of variable lift force is reduced when the gap separation between the main and control cylinders is increased. When compared to solo cylinder values, it is found that the presence of small control cylinders in the flow field results in a considerable reduction of flow-induced forces. The SFDF flow regime was determined to have the lowest fluid forces compared to the other flow regimes studied. Our findings highlight the efficacy of small control cylinders in mitigating flow-induced forces and controlling flow characteristics. The LBM proves to be a valuable computational technique for such fluid flow problems.
本研究使用格子玻尔兹曼方法（LBM）研究了小型控制圆柱体对方柱周围流体动力学的影响。将主圆柱体和控制圆柱体之间的间隙（L）从0变化到6，识别出四种不同的流动状态：单体状态（SBR）、剪切层重新附着（SLR）、抑制充分发展流动（SFDF）和间歇性脱落（IS）。控制圆柱体的存在导致流动诱导力显著降低，阻力系数（CD）以及阻力和升力系数的均方根值（CD和CL）分别降低约31%、90%和81%。与其他状态相比，SFDF流动状态表现出最低的流体力。在本研究工作中，使用格子玻尔兹曼方法（LBM）研究了微小控制圆柱体对方柱流体流动特性的影响。主圆柱体和控制圆柱体之间的间隙（L）在0到6的范围内变化。每个控制圆柱体的尺寸等于主圆柱体的五分之一。根据研究结果，随着间隙间距的变化，存在四种不同的流动状态：间隙间距范围为0≤L≤0.2、0.3≤L≤0.9、1≤L≤3和3.2≤L≤6时，分别为单体状态（SBR）、剪切层重新附着（SLR）、抑制充分发展流动（SFDF）和间歇性脱落（IS）。此外，已经注意到，当主圆柱体和控制圆柱体之间的间隙增大时，可变升力的幅度会减小。与单个圆柱体的值相比，发现流场中存在小型控制圆柱体可导致流动诱导力显著降低。与所研究的其他流动状态相比，确定SFDF流动状态具有最低的流体力。我们的研究结果突出了小型控制圆柱体在减轻流动诱导力和控制流动特性方面的有效性。对于此类流体流动问题，LBM被证明是一种有价值的计算技术。
