dimensionless number

简明释义

无因次值

英英释义

例句

1.The Strouhal number is a dimensionless number used to describe oscillating flow mechanisms.

斯特劳哈尔数是一个用于描述振荡流动机制的无量纲数。

2.The Reynolds number is a crucial dimensionless number that helps predict flow patterns in different fluid flow situations.

雷诺数是一个重要的无量纲数，有助于预测不同流体流动情况中的流动模式。

3.In engineering, the Froude number is a dimensionless number that compares inertial and gravitational forces.

在工程学中，弗劳德数是一个比较惯性和重力作用的无量纲数。

4.The Weber number is a dimensionless number that indicates the relative importance of inertial forces to surface tension forces.

韦伯数是一个表示惯性力与表面张力相对重要性的无量纲数。

5.In heat transfer calculations, the Nusselt number is a dimensionless number that signifies the ratio of convective to conductive heat transfer.

在热传递计算中，努塞尔数是一个无量纲数，表示对流与导热的比率。

作文

In the field of science and engineering, the concept of a dimensionless number plays a crucial role in simplifying complex systems and facilitating comparisons across different scenarios. A dimensionless number is a quantity without any physical units, meaning it is a pure number that results from the ratio of two or more quantities with the same dimensions. This property allows scientists and engineers to analyze and model various phenomena without the complications that arise from differing units of measurement.One of the most common examples of a dimensionless number is the Reynolds number, which is used in fluid mechanics to predict flow patterns in different fluid flow situations. The Reynolds number is calculated by taking the ratio of inertial forces to viscous forces and can help determine whether a flow will be laminar or turbulent. By using a dimensionless number like the Reynolds number, engineers can apply the same principles to a wide range of fluids, regardless of their specific properties, thus making it easier to design systems such as pipelines, aircraft, and even weather models.Another important dimensionless number is the Mach number, which is the ratio of the speed of an object to the speed of sound in the surrounding medium. This number is particularly significant in aerospace engineering, where understanding the behavior of aircraft and spacecraft at various speeds is essential for safety and performance. By analyzing the Mach number, engineers can predict shock waves and other critical phenomena that occur when an object approaches or exceeds the speed of sound.The usefulness of dimensionless numbers extends beyond fluid dynamics and aerodynamics. In heat transfer, the Nusselt number serves as a dimensionless number that relates convective and conductive heat transfer. Similarly, the Prandtl number, another dimensionless number, compares the rate of momentum diffusion to thermal diffusion, providing insights into the behavior of fluids under varying thermal conditions. These dimensionless numbers enable engineers to create correlations and models that can be universally applied, regardless of the specific characteristics of the materials involved.Moreover, dimensionless numbers are not limited to traditional engineering fields; they also find applications in biology, chemistry, and environmental science. For instance, the Péclet number, which is used to characterize the relative importance of convection to diffusion in transport processes, is vital in ecological modeling and understanding pollutant dispersion in natural waters. By employing dimensionless numbers, researchers can develop generalized models that can be applied to various biological systems, enhancing our understanding of complex interactions in ecosystems.In conclusion, the significance of dimensionless numbers in science and engineering cannot be overstated. They provide a means of simplifying complex relationships, allowing for easier analysis and comparison across different systems. By eliminating the complications associated with units of measurement, dimensionless numbers enable researchers and engineers to focus on the underlying principles governing the phenomena they study. As we continue to advance in various scientific disciplines, the role of dimensionless numbers will undoubtedly remain pivotal in driving innovation and understanding in a multitude of fields.

在科学和工程领域，无量纲数的概念在简化复杂系统和促进不同场景之间的比较方面发挥着至关重要的作用。无量纲数是一个没有任何物理单位的量，这意味着它是一个纯数字，由两个或多个具有相同维度的量的比值得出。这一特性使得科学家和工程师能够分析和建模各种现象，而不必面对不同测量单位带来的复杂性。最常见的一个无量纲数的例子是雷诺数，它用于流体力学中预测不同流体流动情况下的流动模式。雷诺数是通过取惯性力与粘性力的比率来计算的，可以帮助确定流动是层流还是湍流。通过使用像雷诺数这样的无量纲数，工程师可以将相同的原则应用于各种流体，无论其具体特性如何，从而更容易设计管道、飞机甚至天气模型等系统。另一个重要的无量纲数是马赫数，它是物体速度与周围介质中声速的比率。这个数字在航空工程中尤为重要，因为理解飞机和航天器在不同速度下的行为对于安全和性能至关重要。通过分析马赫数，工程师可以预测当物体接近或超过声速时发生的冲击波和其他关键现象。无量纲数的有用性不仅限于流体动力学和空气动力学。在热传递中，努塞尔特数作为一个无量纲数，将对流和导热联系起来。同样，普朗特数，另一个无量纲数，比较动量扩散与热扩散的速率，为在不同热条件下流体的行为提供洞察。这些无量纲数使得工程师能够创建可以普遍应用的关联和模型，而不论所涉及材料的具体特性。此外，无量纲数不仅限于传统的工程领域；它们还在生物学、化学和环境科学中找到了应用。例如，Péclet数用于表征对流与扩散在传输过程中的相对重要性，对于生态建模和理解污染物在自然水体中的扩散至关重要。通过采用无量纲数，研究人员能够开发出通用模型，这些模型可以应用于各种生物系统，从而增强我们对生态系统中复杂相互作用的理解。总之，无量纲数在科学和工程中的重要性不容小觑。它们提供了一种简化复杂关系的方法，使得分析和比较不同系统变得更加容易。通过消除与测量单位相关的复杂性，无量纲数使研究人员和工程师能够专注于支配他们研究的现象的基本原理。随着我们在各个科学学科的不断进步，无量纲数的作用无疑将在推动创新和理解众多领域中保持关键地位。