合板中的动态接口行为:通过基于弹的模型研究Lamb波模式排斥
Marcel Nicolai1, Jannis Bulling1, M M Narayanan1
1Federal Institute for Material Research and Testing, Berlin, Germany.
Ultrasonics
|September 7, 2025
概括
在Lamb波中模式排斥是由接口刚度和板块振荡解释的. 这项研究为先进的材料表征和非破坏性评估提供了洞察力.
科学领域:
- 固体机械学 固体机械学
- 波浪传播 波浪传播
- 材料科学 材料科学 材料科学
背景情况:
- 羔羊波对于非破坏性评估至关重要.
- 了解合结构中的波浪行为是复杂的.
- 模式排斥现象需要详细调查.
研究的目的:
- 为了研究合板中的Lamb波的模式排斥.
- 分析接口刚度对模式分离的影响.
- 解释模式排斥的基本动态.
主要方法:
- 使用基于弹的合模型.
- 采用了缩放边界有限元素方法 (SBFEM).
- 在不同的接口条件下分析分散曲线 (弱,滑动,完美合).
主要成果:
- 接口刚度直接影响模式分离和排斥.
- 由于板块振荡,在排斥区域发现了独特的动态行为.
- 在弹性接口内以特定的应变模式连接模式排斥.
结论:
- 在合的Lamb波系统中为模式排斥提供了物理基础的解释.
- 建立了在材料特征化中使用模式排斥的理论基础.
- 突出了增强非破坏性评估技术的潜力.
相关概念视频
Magnetic Damping
1.0K
Eddy currents can produce significant drag on motion, called magnetic damping. For instance, when a metallic pendulum bob swings between the poles of a strong magnet, significant drag acts on the bob as it enters and leaves the field, quickly damping the motion.
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
1.0K
Standing Waves in a Cavity
1.4K
A household microwave and lasers are examples of standing electromagnetic waves in a cavity. When two conducting metal plates are placed parallel at the nodal planes, it creates a cavity where standing waves are formed. The cavity between the two planes is analogous to a stretched string held at the points x = 0 and x = L. Here, the distance 'L' between the two planes must be an integer multiple of half of the wavelength. The wavelengths that satisfy this condition are given by:
1.4K
Damped Oscillations
6.8K
In the real world, oscillations seldom follow true simple harmonic motion. A system that continues its motion indefinitely without losing its amplitude is termed undamped. However, friction of some sort usually dampens the motion, so it fades away or needs more force to continue. For example, a guitar string stops oscillating a few seconds after being plucked. Similarly, one must continually push a swing to keep a child swinging on a playground.
Although friction and other non-conservative...
Although friction and other non-conservative...
6.8K
Forced Oscillations
7.7K
When an oscillator is forced with a periodic driving force, the motion may seem chaotic. The motions of such oscillators are known as transients. After the transients die out, the oscillator reaches a steady state, where the motion is periodic, and the displacement is determined.
7.7K
Types of Damping
7.5K
If the amount of damping in a system is gradually increased, the period and frequency start to become affected because damping opposes, and hence slows, the back and forth motion (the net force is smaller in both directions). If there is a very large amount of damping, the system does not even oscillate; instead, it slowly moves toward equilibrium. In brief, an overdamped system moves slowly towards equilibrium, whereas an underdamped system moves quickly to equilibrium but will oscillate about...
7.5K
Design Example: Underdamped Parallel RLC Circuit
632
Consider designing an oscillator circuit, a crucial component in various electronic devices and systems. The objective is to create an oscillator circuit with specific characteristics: a damped natural frequency of 4 kHz and a damping factor of 4 radians per second. To accomplish this, a parallel RLC circuit is employed, known for its ability to sustain oscillations at a resonant frequency. In this case, the damping factor is pivotal in achieving the desired performance.
Starting with a fixed...
Starting with a fixed...
632


