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“apparent mass lift”是什么意思?

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发表于 2007-4-11 17:23:07 | 显示全部楼层 |阅读模式

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谁可以帮忙解答一下啊?
物理意义、定义什么的
 楼主| 发表于 2007-4-21 16:15:59 | 显示全部楼层

“apparent mass lift”是什么意思?

有些文献里时常看到,
下面是google到的:http://flux.aps.org/meetings/YR01/DFD01/abs/S590002.html
Apparent mass in viscous, vortical flows
Flavio Noca (Jet Propulsion Laboratory)
The concept of added, virtual, apparent, or additional mass is well known in potential flow theory. It is added mass (or more exactly, the time derivative of virtual momentum) that wholly contributes to fluid dynamic forces in unsteady, potential flow configurations. While the force contribution from added mass can be easily evaluated in potential flows, it has always been thought that in real (vortical and viscous) flows, the contribution of added mass to the fluid dynamic force is intertwined in a complex way with the force resulting from wake and boundary layer vorticity. Recently, Shiels, Leonard, and Roshko (Journal of Fluids and Structures, vol 15, pp 3-21, 2001) [henceforth SLR] showed that the fluid dynamic lift force on a circular cylinder performing transverse oscillations in a steady stream can actually be decomposed into a lift force due to apparent mass (as evaluated from potential theory) and a ``wake';'; force resulting from frictional as well as altered pressure forces caused by the boundary layer and wake growth in viscous flow. Through a rigorous formalism analogous to SLR’s, we will confirm that the SLR decomposition is correct and valid for any body shape in arbitrary motion. The SLR decomposition is a seminal discovery in the science of unsteady aero/hydrodynamics, as it allows to clearly distinguish the force contributions from added mass and from the ``wake';';. The result is particularly important for understanding the flight and swimming mechanics of animals.
还是不懂什么意思。。。
发表于 2007-4-25 13:02:27 | 显示全部楼层

“apparent mass lift”是什么意思?

“附加质量升力”,apparent mass是“附加质量”的意思。
 楼主| 发表于 2007-4-25 17:37:48 | 显示全部楼层

“apparent mass lift”是什么意思?

但不知道它的物理意义是什么
不明白什么是"附加质量升力"
发表于 2007-5-23 21:06:48 | 显示全部楼层

“apparent mass lift”是什么意思?

在无粘流计算中无法计入粘性阻力,包括压差阻力,因此在物体运动时虽然无粘流场的压强场可以算出,但是依此算出的物体加速度必然因为忽略了粘性阻力而有所加大。为了去掉这种误差,就假设物体的质量有一个附加量,这样在忽略了粘性阻力后仍然可以得到大致相同的加速度,这个质量附加量就是附加质量,总的质量就是名义质量。显然附加质量是人为假设的一个质量,实际上是不存在的,因此相关的总质量只能被称为是名义质量。
发表于 2007-8-31 00:55:54 | 显示全部楼层

“apparent mass lift”是什么意思?

楼上的,不懂就不要乱讲,附加质量不是你说的那个含义。由于物体在流体中
作速度和角速度有变化,因此,导致相应的流体出现速度和角速度的变化,流体会对物体产生一个反作用力。将这个力折合在运动的物体上,成为附加质量
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