在网格博尔兹曼框架内的不可压缩流的大模拟的子网格尺度模型
Heng Zhang1, Haibao Hu1, Fan Zhang1
1School of Marine Science and Technology, <a href="https://ror.org/01y0j0j86">Northwestern Polytechnical University</a>, Xi'an, Shaanxi 710072, People's Republic of China.
Physical review. E
|November 20, 2024
概括
一个新的合算法结合了不平衡时刻和体积应变拉伸模型,以使用格子博尔茨曼法进行准确和高效的大模拟.
科学领域:
- 计算流体动力学的流体动力学.
- 流建模 流建模
背景情况:
- 大模拟 (LES) 对于准确高效的流分析至关重要.
- 将先进的流模型集成到诸如格子博尔茨曼法 (LBM) 这样的数值方法中,带来了计算挑战.
研究的目的:
- 为 LES 提出和验证一个新的合算法.
- 在LBM框架内结合不平衡时刻 (NM) 和体积应变拉伸 (VSS) 模型.
- 为了提高流模拟的准确性和效率.
主要方法:
- 通过专门的VSS模型计算和查普曼-恩斯科格分析开发了一种合算法,将NM和的粘度联系起来.
- 在格子博尔茨曼方法 (LBM) 中实现了算法.
- 用直接数值模拟 (DNS) 验证了对三个基准流情况的方法.
主要成果:
- 与DNS相比,拟议的合算法表现出高精度和高效率.
- 在每个网点实现了对旋粘度的统一计算格式.
- 该方法优化了内存访问,利用LBM的并行性,并比中央差异方法提高了20%的计算效率.
结论:
- 在LBM内合的NM-VSS算法提供了一个准确而高效的LES方法.
- 该方法的本地计算和优化的内存访问增强了其实际适用性.
- 这项工作在LBM框架内推进了流模拟能力.
相关概念视频
Laminar and Turbulent Flow
8.4K
Fluid dynamics is the study of fluids in motion. Velocity vectors are often used to illustrate fluid motion in applications like meteorology. For example, wind—the fluid motion of air in the atmosphere—can be represented by vectors indicating the speed and direction of the wind at any given point on a map. Another method for representing fluid motion is a streamline. A streamline represents the path of a small volume of fluid as it flows. When the flow pattern changes with time, the...
8.4K
Typical Model Studies
340
Fluid mechanics model studies often utilize scaled-down systems to predict fluid behavior in full-scale environments, such as river flows, dam spillways, and structures interacting with open surfaces. Maintaining Froude number similarity in river models is crucial, as it replicates surface flow features like wave patterns and velocities.
340
Steady, Laminar Flow Between Parallel Plates
141
Understanding steady, laminar flow between parallel plates is essential for analyzing and designing flow in narrow rectangular channels, commonly found in various water conveyance and drainage systems. The Navier-Stokes equations govern fluid motion and are generally challenging to solve due to their nonlinearity. However, simplifications are possible in certain cases, like the steady laminar flow between parallel plates. For this scenario, we assume steady, incompressible, laminar flow.
141
Navier–Stokes Equations
428
For incompressible Newtonian fluids, where density remains constant, stresses show a linear relationship with the deformation rate, defined by normal and shear stresses. Normal stresses depend on the pressure exerted on the fluid and the rate of deformation in specific directions, which determines how fluid flows under varying pressures. Shear stresses, on the other hand, act tangentially across fluid layers. They explain how adjacent fluid layers slide relative to one another, connecting...
428
Modeling and Similitude
245
Scaled modeling is a fundamental technique in engineering, enabling the study of large and complex systems by creating smaller, manageable replicas that recreate critical characteristics of the original. In hydrology and civil infrastructure, for example, scaled models of dams help analyze water flow, turbulence, and pressure. This method allows for accurate predictions of real-world behavior within a controlled environment, significantly reducing the cost and time involved in full-scale...
245
Eulerian and Lagrangian Flow Descriptions
1.0K
Fluid flow analysis is critical in many scientific and engineering disciplines, and two principal approaches are used to describe this flow: the Eulerian and Lagrangian methods. These methods offer different perspectives on monitoring and analyzing the motion of fluids, each with distinct advantages depending on the scenario.
The Eulerian method focuses on fixed points in space where fluid properties, such as velocity, pressure, and temperature, are observed as the fluid moves between these...
The Eulerian method focuses on fixed points in space where fluid properties, such as velocity, pressure, and temperature, are observed as the fluid moves between these...
1.0K


