non-dimensional parameter

简明释义

无因次参数

英英释义

例句

1.In structural engineering, the slenderness ratio is a non-dimensional parameter that indicates the stability of columns.

在结构工程中，细长比是一个无量纲参数，它指示柱子的稳定性。

2.In fluid dynamics, the Reynolds number is a key non-dimensional parameter that helps predict flow patterns in different fluid flow situations.

在流体动力学中，雷诺数是一个关键的无量纲参数，它有助于预测不同流动情况下的流动模式。

3.The Froude number is a non-dimensional parameter that compares inertial and gravitational forces in fluid motion.

弗劳德数是一个无量纲参数，它比较了流体运动中的惯性力和重力。

4.The Strouhal number is another important non-dimensional parameter used in the study of oscillating flows.

斯特劳哈尔数是另一个重要的无量纲参数，用于研究振荡流动。

5.When analyzing heat transfer, the Nusselt number serves as a non-dimensional parameter to characterize convective heat transfer.

在分析热传递时，努塞尔数作为一个无量纲参数来表征对流热传递。

作文

In the realm of physics and engineering, understanding complex systems often requires simplifying them into more manageable forms. One powerful tool in this simplification process is the concept of a non-dimensional parameter. A non-dimensional parameter is a quantity that does not have any physical units associated with it; instead, it is a pure number that provides insight into the relationships between different physical quantities. This concept plays a crucial role in various fields, including fluid dynamics, heat transfer, and structural analysis.To illustrate the significance of a non-dimensional parameter, let’s consider the example of fluid flow. In fluid dynamics, the Reynolds number is a well-known non-dimensional parameter that helps predict flow patterns in different fluid flow situations. The Reynolds number is defined as the ratio of inertial forces to viscous forces and is calculated using the formula:Re = (ρ * v * L) / μwhere ρ is the fluid density, v is the velocity of the fluid, L is a characteristic length (such as diameter), and μ is the dynamic viscosity. The resulting Reynolds number allows engineers to categorize the flow as laminar or turbulent without needing to delve into the specific units of each variable involved. This categorization is essential for designing efficient systems, such as pipelines or aircraft wings.Another critical application of non-dimensional parameters is in heat transfer. The Nusselt number, another non-dimensional parameter, characterizes convective heat transfer relative to conductive heat transfer. It is instrumental in determining how effectively heat is transferred in various thermal systems. The Nusselt number is defined as:Nu = (h * L) / kwhere h is the convective heat transfer coefficient, L is the characteristic length, and k is the thermal conductivity of the fluid. By using the Nusselt number, engineers can assess the efficiency of heat exchangers and other thermal systems without getting bogged down by the complexities of unit conversions.The beauty of non-dimensional parameters lies in their ability to reduce the complexity of physical phenomena into simpler forms that can be universally understood and compared. They provide a means to scale problems and solutions across different systems and conditions. For example, by utilizing non-dimensional parameters, researchers can develop generalized correlations that apply to a wide range of scenarios, enhancing predictive capabilities and facilitating better design practices.Furthermore, non-dimensional parameters are integral to dimensional analysis, a mathematical technique that helps engineers and scientists understand the relationships between different physical quantities. Dimensional analysis allows for the identification of key non-dimensional parameters that govern the behavior of a system, leading to more effective modeling and simulation. This approach is particularly valuable in experimental studies, where it can guide the design of experiments and the interpretation of results.In conclusion, the concept of a non-dimensional parameter is vital for simplifying complex systems in physics and engineering. By transforming physical quantities into dimensionless numbers, engineers and scientists can better understand the relationships between different variables, predict system behavior, and improve design efficiency. Whether through the Reynolds number in fluid dynamics or the Nusselt number in heat transfer, non-dimensional parameters provide a universal language for describing and analyzing physical phenomena, making them an indispensable part of scientific inquiry and engineering practice.

在物理和工程领域，理解复杂系统通常需要将其简化为更易于管理的形式。这个简化过程中的一个强大工具是无量纲参数的概念。无量纲参数是指没有任何物理单位相关联的量；相反，它是一个纯数字，提供了对不同物理量之间关系的洞察。这个概念在流体动力学、热传递和结构分析等多个领域中发挥着至关重要的作用。为了说明无量纲参数的重要性，让我们考虑流体流动的例子。在流体动力学中，雷诺数是一个众所周知的无量纲参数，它有助于预测不同流体流动情况下的流动模式。雷诺数定义为惯性力与粘性力的比率，可以使用以下公式计算：Re = (ρ * v * L) / μ其中，ρ是流体密度，v是流体速度，L是特征长度（如直径），μ是动态粘度。得到的雷诺数使工程师能够在不需要深入了解每个变量涉及的具体单位的情况下，对流动进行层流或湍流的分类。这种分类对于设计高效的系统（如管道或飞机机翼）至关重要。无量纲参数的另一个重要应用是在热传递中。努塞尔数是另一个无量纲参数，它表征了对流热传递相对于导热传递的效率。在确定各种热系统中热量传递的有效性时，它是非常重要的。努塞尔数的定义为：Nu = (h * L) / k其中，h是对流换热系数，L是特征长度，k是流体的热导率。通过使用努塞尔数，工程师可以评估热交换器和其他热系统的效率，而无需陷入单位转换的复杂性。无量纲参数的美在于它们能够将物理现象的复杂性简化为更简单的形式，这些形式可以被普遍理解和比较。它们提供了一种跨越不同系统和条件缩放问题和解决方案的方法。例如，通过利用无量纲参数，研究人员可以开发适用于广泛场景的通用关联，从而增强预测能力并促进更好的设计实践。此外，无量纲参数是维度分析的重要组成部分，这是一种数学技术，帮助工程师和科学家理解不同物理量之间的关系。维度分析允许识别主导系统行为的关键无量纲参数，从而导致更有效的建模和仿真。这种方法在实验研究中尤其有价值，因为它可以指导实验设计和结果解释。总之，无量纲参数的概念对于简化物理和工程中的复杂系统至关重要。通过将物理量转化为无量纲数字，工程师和科学家能够更好地理解不同变量之间的关系，预测系统行为并提高设计效率。无论是流体动力学中的雷诺数，还是热传递中的努塞尔数，无量纲参数为描述和分析物理现象提供了通用语言，使其成为科学探究和工程实践中不可或缺的一部分。