boundary layer

简明释义

边层

英英释义

例句

1.In aerodynamics, the boundary layer affects drag and lift on an aircraft.

在空气动力学中，边界层影响飞机的阻力和升力。

2.Engineers often study the boundary layer to improve the efficiency of wind turbines.

工程师们常常研究边界层以提高风力涡轮机的效率。

3.The thickness of the boundary layer can change with different flow velocities.

随着不同流速的变化，边界层的厚度也会改变。

4.The concept of the boundary layer is crucial in understanding fluid dynamics.

理解流体动力学时，边界层的概念至关重要。

5.During a storm, the boundary layer can influence weather patterns significantly.

在暴风雨期间，边界层可以显著影响天气模式。

作文

The concept of the boundary layer is fundamental in fluid dynamics and plays a crucial role in various engineering applications. In simple terms, the boundary layer refers to the thin region of fluid that is adjacent to a solid surface, where the effects of viscosity are significant. This layer is critical because it affects how fluids flow over surfaces, which can impact drag forces, heat transfer, and mass transfer.When a fluid flows over a flat plate, for instance, the velocity of the fluid near the surface is significantly lower than that of the free stream fluid due to viscous forces. This phenomenon creates a gradient of velocity from zero at the surface (where the fluid is stationary) to the free stream velocity away from the surface. The thickness of this boundary layer increases with distance from the leading edge of the plate, which can be described mathematically using the Navier-Stokes equations.Understanding the boundary layer is essential for engineers and scientists as it has practical implications in aerodynamics, hydrodynamics, and thermal systems. For example, in the design of aircraft wings, the characteristics of the boundary layer can determine the lift and drag experienced by the wing. If the boundary layer remains attached to the wing surface, it can enhance lift; however, if it separates, it can lead to increased drag and loss of control.Moreover, the boundary layer concept is not limited to air or water; it also applies to other contexts, such as heat exchangers, where understanding the thermal boundary layer can optimize energy efficiency. The temperature gradient within the boundary layer affects how effectively heat is transferred between fluids.In environmental science, the boundary layer is crucial for understanding pollutant dispersion in the atmosphere. The characteristics of the atmospheric boundary layer influence how pollutants spread and dilute, affecting air quality and climate models. Thus, studying the boundary layer helps in developing strategies to mitigate pollution and its impacts on health and the environment.In conclusion, the boundary layer is a vital concept across various fields of study. Its implications extend from improving engineering designs to understanding environmental phenomena. By grasping the principles governing the boundary layer, we can better predict and manage fluid behavior in numerous applications, ultimately leading to advancements in technology and environmental stewardship.

边界层的概念在流体动力学中是基础，并在各种工程应用中发挥着关键作用。简单来说，边界层是指邻近固体表面的薄流体区域，在该区域内，粘性效应显著。这个层次至关重要，因为它影响流体如何在表面上流动，这会影响阻力、热传递和质量传递。例如，当流体在平板上流动时，靠近表面的流体速度明显低于自由流动的流体速度，这是由于粘性力的作用。这种现象在表面处产生了零速度的梯度，到离表面较远的自由流速度。这个边界层的厚度随着距离板前缘的增加而增加，可以使用纳维-斯托克斯方程进行数学描述。理解边界层对工程师和科学家至关重要，因为它在空气动力学、水动力学和热系统中具有实际意义。例如，在飞机机翼的设计中，边界层的特性可以决定机翼所经历的升力和阻力。如果边界层保持附着在机翼表面，它可以增强升力；然而，如果它分离，它可能导致阻力增加和控制丧失。此外，边界层的概念不仅限于空气或水；它还适用于其他上下文，例如热交换器，在那里理解热边界层可以优化能量效率。边界层内的温度梯度影响热量在流体之间传递的有效性。在环境科学中，边界层对于理解大气中污染物的扩散至关重要。大气边界层的特性影响污染物的传播和稀释，影响空气质量和气候模型。因此，研究边界层有助于制定减轻污染及其对健康和环境影响的策略。总之，边界层是各个研究领域的重要概念。它的影响从改善工程设计到理解环境现象。通过掌握支配边界层的原理，我们可以更好地预测和管理各种应用中的流体行为，最终推动技术进步和环境保护。