dimensionless number

简明释义

1. 无量纲数; 2. 无因次数;

英英释义

例句

1.The Strouhal number is another important dimensionless number 无量纲数 that helps in analyzing oscillating flow phenomena.

斯特劳哈尔数是另一个重要的无量纲数 dimensionless number，有助于分析振荡流动现象。

2.The Froude number is a dimensionless number 无量纲数 that compares inertial and gravitational forces in fluid flow.

弗劳德数是一个无量纲数 dimensionless number，用于比较流体流动中的惯性和重力作用。

3.In chemical engineering, the Schmidt number is a dimensionless number 无量纲数 that characterizes mass transfer in a fluid.

在化工工程中，施密特数是一个无量纲数 dimensionless number，用于表征流体中的质量传递。

4.The Reynolds number is a key dimensionless number 无量纲数 used in fluid mechanics to predict flow patterns in different fluid flow situations.

雷诺数是流体力学中一个关键的无量纲数 dimensionless number，用于预测不同流体流动情况下的流动模式。

5.In heat transfer, the Nusselt number is a dimensionless number 无量纲数 that indicates the efficiency of convective heat transfer.

在热传递中，努塞尔数是一个无量纲数 dimensionless number，表示对流热传递的效率。

作文

In the realm of science and engineering, the concept of a dimensionless number plays a crucial role in simplifying complex phenomena. A dimensionless number is a numerical value that has no units associated with it, allowing for the comparison of different systems without the complications introduced by varying units of measurement. These numbers are particularly useful in fluid mechanics, thermodynamics, and other fields where the relationships between physical quantities can be intricate and difficult to analyze directly.For instance, consider the Reynolds number, which is a well-known dimensionless number used in fluid dynamics. The Reynolds number is defined as the ratio of inertial forces to viscous forces and helps predict flow patterns in different fluid flow situations. By using this dimensionless number, engineers can determine whether a flow will be laminar or turbulent, which is essential for designing efficient systems such as pipelines, aircraft, and even weather prediction 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 dimensionless number is critical in aerodynamics, especially when designing vehicles that travel at high speeds. Understanding the Mach number allows engineers to anticipate shock waves and other aerodynamic effects that occur when an object approaches or exceeds the speed of sound.The significance of dimensionless numbers extends beyond just fluid dynamics. In heat transfer, the Nusselt number is a dimensionless number that measures the enhancement of heat transfer through a fluid as a result of convection compared to conduction alone. Similarly, the Prandtl number, another dimensionless number, relates the rate of momentum diffusion to the rate of thermal diffusion in a fluid. These numbers allow engineers and scientists to correlate experimental results with theoretical predictions, thereby facilitating the design of more efficient thermal systems.Moreover, dimensionless numbers enable researchers to create scaling laws that can predict the behavior of larger systems based on smaller models. This is particularly valuable in experimental fluid dynamics, where it may be impractical or impossible to replicate the conditions of a full-scale system. By ensuring that the dimensionless numbers are consistent between the model and the prototype, researchers can confidently extrapolate their findings from one scale to another.In conclusion, the concept of a dimensionless number is fundamental to various scientific and engineering disciplines. By providing a means to compare and analyze different systems without the complications of units, these numbers simplify complex relationships and enhance our understanding of physical phenomena. As technology advances and new challenges arise, the importance of dimensionless numbers will only continue to grow, underscoring their vital role in the pursuit of knowledge and innovation in science and engineering.

在科学和工程的领域中，无量纲数的概念在简化复杂现象方面发挥着至关重要的作用。无量纲数是一个没有单位的数值，这使得在不同系统之间进行比较时，不会因为测量单位的不同而引入复杂性。这些数字在流体力学、热力学以及其他物理量之间关系可能复杂且难以直接分析的领域中尤其有用。例如，考虑雷诺数，这是流体动力学中一个众所周知的无量纲数。雷诺数被定义为惯性力与粘性力的比率，有助于预测不同流体流动情况中的流动模式。通过使用这个无量纲数，工程师可以确定流动是层流还是湍流，这对于设计高效的系统（如管道、飞机甚至天气预测模型）至关重要。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。这个无量纲数在空气动力学中至关重要，特别是在设计高速行驶的交通工具时。理解马赫数使工程师能够预测当物体接近或超过声速时发生的冲击波和其他空气动力学效应。无量纲数的重要性不仅限于流体动力学。在热传递中，努塞尔数是一个无量纲数，它衡量通过流体的热传递相对于单独导热的增强程度。同样，普朗特数是另一个无量纲数，它将动量扩散速率与流体中的热扩散速率联系起来。这些数字使工程师和科学家能够将实验结果与理论预测相关联，从而促进更高效热系统的设计。此外，无量纲数使研究人员能够创建缩放法则，可以根据较小的模型预测较大系统的行为。这在实验流体动力学中尤为宝贵，因为在全尺度系统中重现条件可能不切实际或不可能。通过确保模型和原型之间的无量纲数一致，研究人员可以自信地将他们的发现从一个规模推断到另一个规模。总之，无量纲数的概念是各种科学和工程学科的基础。通过提供一种在没有单位复杂性的情况下比较和分析不同系统的方法，这些数字简化了复杂关系，并增强了我们对物理现象的理解。随着技术的进步和新挑战的出现，无量纲数的重要性只会继续增长，强调了它们在科学和工程知识与创新追求中的重要角色。