lift coefficient

简明释义

升力系数

英英释义

例句

1.Engineers use the lift coefficient to optimize wing designs for better fuel efficiency.

工程师使用升力系数来优化机翼设计，以提高燃油效率。

2.During testing, we found that increasing the flaps resulted in a higher lift coefficient at lower speeds.

在测试中，我们发现增加襟翼在较低速度下导致更高的升力系数。

3.The aircraft's performance is greatly influenced by its lift coefficient, which determines how much lift is generated at a given angle of attack.

飞机的性能受到其升力系数的重大影响，后者决定在给定攻角下产生多少升力。

4.The lift coefficient can vary significantly between different aircraft models.

不同飞机型号之间的升力系数可能会有显著差异。

5.A higher lift coefficient allows for shorter takeoff distances.

更高的升力系数允许更短的起飞距离。

作文

The concept of the lift coefficient is fundamental in the field of aerodynamics. It is a dimensionless number that helps quantify the lift force generated by an airfoil or wing at a given angle of attack. Understanding the lift coefficient is crucial for engineers and designers who work on aircraft, as it directly influences the performance and efficiency of the vehicle. The lift coefficient can be defined mathematically as the ratio of the lift force to the product of the air density, the square of the velocity, and the reference area of the wing. By analyzing this coefficient, one can determine how well a wing performs under various flight conditions.In practical terms, the lift coefficient varies with the angle of attack, which is the angle between the chord line of the wing and the oncoming airflow. At low angles of attack, the lift coefficient increases steadily, allowing the wing to generate more lift. However, as the angle of attack increases beyond a certain point, the lift coefficient reaches a maximum value and then begins to decrease, indicating that the wing is approaching stall conditions. This behavior is critical for pilots to understand, as exceeding the critical angle of attack can lead to a loss of control.Moreover, the lift coefficient is influenced by several factors, including the shape of the wing, the surface roughness, and the Reynolds number, which characterizes the flow regime around the airfoil. For instance, a cambered wing typically has a higher lift coefficient compared to a flat plate at the same angle of attack. This is because the curvature of the wing allows for smoother airflow and reduced turbulence, resulting in enhanced lift generation.In the design phase of an aircraft, engineers conduct extensive wind tunnel testing to measure the lift coefficient across various configurations and conditions. These tests provide invaluable data that inform design decisions, such as wing shape, size, and material selection. Additionally, computational fluid dynamics (CFD) simulations are often employed to predict the lift coefficient and visualize airflow patterns around the aircraft.Understanding the lift coefficient is not limited to aviation; it also has applications in other fields, such as automotive engineering and marine design. For example, in the automotive industry, the lift coefficient is used to evaluate the aerodynamic performance of vehicles, impacting fuel efficiency and stability at high speeds. Similarly, in marine design, understanding how hull shapes affect the lift coefficient can lead to more efficient ship designs.In conclusion, the lift coefficient is a vital parameter in aerodynamics that plays a significant role in the performance of wings and airfoils. Its understanding is essential for anyone involved in the design and operation of aircraft, as well as in other engineering disciplines. By mastering the principles surrounding the lift coefficient, engineers can optimize designs for improved performance, safety, and efficiency, ultimately contributing to advancements in technology and transportation.

升力系数的概念在空气动力学领域中是基础性的。它是一个无量纲数，帮助量化在给定攻角下由翼型或机翼产生的升力。理解升力系数对从事飞机设计和工程的工程师至关重要，因为它直接影响到飞机的性能和效率。升力系数可以通过数学公式定义为升力与空气密度、速度平方和机翼参考面积的乘积的比率。通过分析这个系数，可以确定机翼在各种飞行条件下的表现。在实际应用中，升力系数随着攻角的变化而变化，攻角是机翼弦线与来流之间的角度。在低攻角时，升力系数稳步增加，使机翼产生更多的升力。然而，随着攻角超过某个点，升力系数达到最大值后开始下降，表明机翼接近失速状态。这种行为对于飞行员来说至关重要，因为超过临界攻角可能导致失去控制。此外，升力系数还受到多个因素的影响，包括机翼的形状、表面粗糙度和雷诺数，后者表征了气流在翼型周围的流动状态。例如，在相同攻角下，弯曲翼的升力系数通常高于平板。这是因为机翼的曲率允许气流更平滑地流动并减少湍流，从而增强了升力的生成。在飞机设计阶段，工程师会进行广泛的风洞测试，以测量不同配置和条件下的升力系数。这些测试提供了宝贵的数据，帮助设计决策，例如机翼的形状、大小和材料选择。此外，计算流体动力学（CFD）模拟通常用于预测升力系数并可视化飞机周围的气流模式。理解升力系数不仅限于航空，它在其他领域也有应用，例如汽车工程和海洋设计。例如，在汽车工业中，升力系数用于评估车辆的空气动力性能，影响燃油效率和高速稳定性。同样，在海洋设计中，理解船体形状如何影响升力系数可以导致更高效的船舶设计。总之，升力系数是空气动力学中的一个重要参数，在机翼和翼型的性能中发挥着重要作用。掌握升力系数的原理对于任何参与飞机设计和操作的人都是必不可少的，以及在其他工程学科中。通过精通与升力系数相关的原理，工程师可以优化设计以提高性能、安全性和效率，从而最终促进技术和交通运输的进步。