因此，我将这个博客链接到我的主题爆炸科学与工程 (//m.limpotrade.com//m.limpotrade.com/node/786)

欢迎在我的博客上发表一些东西。万博manbetx平台那里太安静了。

论文已发送至您的邮箱。

请允许我尽我所能回答你。

我想在这里模拟的实际上很简单:

外径为48 mm，内径为12 mm，厚度为0.5 mm的磁盘在ANSYS中使用8节点十六进制元素建模。材料性能定义为玻璃环氧树脂，E = 90 GPa， ν = 0.24， ρ = 2.53 × 10-6 kg/mm3。圆盘内径处的节点受到半正弦加速度冲击，峰值为500G (G = 9.81 m/s2)，持续时间为2毫秒。施加冲击的方向是垂直的或向上的。内径被限制在平移方向上移动，但它可以垂直移动。施加的冲击在2ms时终止，而磁盘响应(变形)是感兴趣的。测量圆盘外径(圆盘尖端)的位移随时间的变化(时程分析)。从这里我们得到了圆盘的冲击响应，用位移表示。 For different element formulation, ANSYS will give different value of displacement. As a benchmark, maximum displacement is 0.1 mm. Damping ratio is not yet included in this simulation. The objective is simply to find tip displacement of the disk with respect to time. The failure of the disk is not yet a consideration, and it is expected that impulse 500G will result in disk deformation only, not failure (break) of the disk.

Second problem is disk with suspension. Below the suspension, between the disk and the suspension, there's a tiny little block called "slider". The slider is flying on the top of the disk when the HDD is in operating condition (meaning: read/write operation is ongoing). The reason why it's flying is because of the air-bearing under the slider. It's built up by the unique contour of air-bearing surface of slider when the air (as a result of spinning disk) is passing it. People may model this air-bearing with spring-damper element. The stiffness (force and moment as well) can be obtained by solving Reynold equations.

The "bearing" that you mentioned could be spindle bearing which holds the disk. Another "bearing" is pivot bearing, where the suspension is attached to.

Zeng and Bogy paper might give you some idea how people use finite element method to solve this problem.

按照您的建议，我又去阅读了一些关于磁盘驱动器的文献。我对这个问题的好奇心是由于我在研究中处理的冲击和流体结构相互作用的组合(在一个完全不同的领域)。如果可以，请把Zeng和Bogy的论文发邮件给我。

我想你们主要对便携式机械用的小磁盘感兴趣。在这种情况下，你提到的那种量级的加速度应该会导致明显的变形——特别是因为圆盘很薄。你有关于变形的数字吗?

当你说…振荡是在冲击终止后发生的，你到底是什么意思?很明显，冲击脉冲会继续向外扩散，反射回来，干扰其他脉冲，等等。但如果你用一种完全弹性的材料，它永远不会受潮。然而，如果材料是耗散的，则磁盘的响应将显着不同。 Are you saying that these effects are not of interest as far as your particular problem is concerned?

I don't really understand what it is that you are trying to find out. Is it whether the disk will break under the impulse? If that is the case, what failure criteria do you use. Or are you trying to find out whether the disk will impact other components of the drive system?

I went and looked up some material on air bearings on the web. From what I gather, these bearings are in the spindle subassembly at the center of the disk. However, the air bearing you are talking about is below the slider. I am confused here and an explanation of the situation will be really helpful.

Biswajit

亲爱的Jun

我对op-shock有一些初步的模拟结果，但我需要进一步"cook"它们以获得更合理的数据。

你是对的，Jun: Bogy小组(加州大学伯克利分校)是这个问题的主要研究人员。其他还有Talke集团(加州大学圣地亚哥分校)，Shu Dongwei(我相信你记得这个名字- NTU)， Yap Fook Fah集团(NTU)， DSI (S'pore)等。他们每个人都有自己的关注点。所以看到这一领域的不断丰富是非常令人兴奋的。

回答您的问题:您可能知道，在冲击期间和之后的飞行高度调制通常由空气轴承刚度(垂直，滚转和俯仰)，酒窝滑块接触，悬架刚度，冲击幅度和持续时间等因素决定。研究认为，空气轴承的非线性对HDD受到高g冲击的影响很大。从数值的角度来看，我想说预处理部分有非常重要的作用;包括为盘状悬挂系统选择合适的元件配方。准确性必须放在第一位; then, we need to make adjustment on solving computational time.

Currently, the gap is in the experimental validation of numerical results. Some people may think that it's not really useful to compare numerical solution and experimental result since both conditions are separated by initial assumptions and unknown factors. Nevertheless, I believe it's still worthwhile to validate numerical results with experiments since we want (at least) to see the trend of the result; not the exact value.

What do you think, Jun?

Indeed, you are again correct. Without any industrial collaboration, the process of getting it done is somehow unsmooth. The research direction may be deflected somewhere else as well.