在五个维度的流
José I Cardesa1, Alberto Vela-Martín2, Javier Jiménez2
1School of Aeronautics, Universidad Politécnica de Madrid, 28040 Madrid, Spain. ji.cardesa@upm.es.
概括
研究人员在流中发现了一种跨尺度的能量联系. 流体能量块在较大的尺度上出现,在较小的尺度上消散,改善了各种流体类型的流模型.
科学领域:
- 流体动力学
- 流研究
- 多尺度物理
背景情况:
- 流显示了能量在不同尺度上的消散.
- 了解能量级联对于地质和工业流量建模至关重要.
研究的目的:
- 在流中检测和描述跨尺度能量转移的统计优势.
- 为开发先进的流模型提供洞察力.
主要方法:
- 在不同的尺度上追踪含有能量的流体区域.
- 分析尺度之间的能量转移的统计优势 (Δ,2Δ,Δ/2).
主要成果:
- 在能源转移中确定了主要的跨度链接.
- 观察到的液体能量块在2Δ尺度出现,在Δ尺度存在,并在Δ/2尺度消散.
- 证明了类似水的液体中的能量布.
结论:
- 这项研究揭示了流中的能量级联的关键机制.
- 这些发现为改善流模型提供了基本的见解.
- 该方法可以扩展到导电流体,量子流体和等离子体.
相关概念视频
Turbulent Flow
795
Turbulent flow is characterized by unpredictable fluctuations in velocity and pressure, which result in a chaotic fluid movement distinct from the orderly patterns of laminar flow. While laminar flow is governed by smooth, parallel layers with minimal mixing, turbulent flow exhibits highly irregular, three-dimensional patterns. This behavior arises due to instabilities in the fluid's velocity profile, and amplifies as the flow velocity increases. Minor disturbances, known as turbulent...
795
Collisions in Multiple Dimensions: Introduction
7.1K
It is far more common for collisions to occur in two dimensions; that is, the initial velocity vectors are neither parallel nor antiparallel to each other. Let's see what complications arise from this. The first idea is that momentum is a vector. Like all vectors, it can be expressed as a sum of perpendicular components (usually, though not always, an x-component and a y-component, and a z-component if necessary). Thus, when the statement of conservation of momentum is written for a...
7.1K
Dimensionless Groups in Fluid Mechanics
852
Dimensionless groups in fluid mechanics provide simplified ratios that help analyze fluid behavior without relying on specific units. The Reynolds number (Re), which represents the ratio of inertial to viscous forces, distinguishes between laminar and turbulent flows, making it essential in the design of pipelines and aerodynamic surfaces. The Froude number (Fr), the ratio of inertial to gravitational forces, is particularly useful in predicting wave formation and hydraulic jumps in...
852
Turbulent Flow: Problem Solving
449
Carbonation is a process used to dissolve carbon dioxide gas in a liquid, commonly used in the production of carbonated beverages. Achieving efficient carbonation requires careful control of temperature, pressure, and flow conditions. By adjusting these parameters, carbonation efficiency can be maximized, producing a higher concentration of CO2 in the liquid.
Temperature is a key factor in CO2 solubility. In this case, the CO2 gas and the liquid are cooled to 20°C. Lower temperatures enhance...
Temperature is a key factor in CO2 solubility. In this case, the CO2 gas and the liquid are cooled to 20°C. Lower temperatures enhance...
449
Collisions in Multiple Dimensions: Problem Solving
5.6K
In multiple dimensions, the conservation of momentum applies in each direction independently. Hence, to solve collisions in multiple dimensions, we should write down the momentum conservation in each direction separately. To help understand collisions in multiple dimensions, consider an example.
A small car of mass 1,200 kg traveling east at 60 km/h collides at an intersection with a truck of mass 3,000 kg traveling due north at 40 km/h. The two vehicles are locked together. What is the...
A small car of mass 1,200 kg traveling east at 60 km/h collides at an intersection with a truck of mass 3,000 kg traveling due north at 40 km/h. The two vehicles are locked together. What is the...
5.6K
Laminar and Turbulent Flow
11.2K
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...
11.2K


