Shock waves in microchannels
Shock waves in microchannels
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微通道中的冲击波
DOI：
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发表时间：
2013
影响因子：
3.7
通讯作者：
Pierre Perrier
中科院分区：
文献类型：
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作者：
G. Mirshekari;M. Brouillette;J. Giordano;Christian Hébert;J. Parisse;Pierre Perrier
一种全仪器化的微型激波管被认为是迄今为止最小的。该装置用于研究在一个大（37毫米）激波管中产生的激波在一个液压直径为34 $ mathm {mu} mathm {m} $和2毫米长的微通道中的传输。设计了一种具有千兆赫带宽的新型压力微传感器，用于获取五轴站微通道冲击波的压力-时间历史。在所有情况下，透射的激波都被发现比入射的激波弱，并且当它沿着微通道传播时，在压力和速度上都被观察到衰减。将这些结果与各种解析模型和数值模型进行了比较，并与假设无滑移等温壁边界条件的Navier-Stokes计算流体力学计算结果最吻合；简单激波管层流边界层模型也得到了很好的一致性。研究还发现，微通道内流动的发展高度依赖于微通道入口的条件，这些条件控制着进入装置的质量通量。无论现有设施的微米尺寸如何，该尺度的微通道中的激波传播表现出与在低压下运行的大型设施中观察到的行为相似，并且激波衰减可以用公认的层流边界模型来解释。
Abstract A fully instrumented microscale shock tube, believed to be the smallest to date, has been fabricated and tested. This facility is used to study the transmission of a shock wave, produced in a large (37 mm) shock tube, into a 34 $mathrm{mu} mathrm{m} $ hydraulic diameter and 2 mm long microchannel. Pressure microsensors of a novel design, with gigahertz bandwidth, are used to obtain pressure–time histories of the microchannel shock wave at five axial stations. In all cases the transmitted shock wave is found to be weaker than the incident shock wave, and is observed to decay both in pressure and velocity as it propagates down the microchannel. These results are compared with various analytical and numerical models, and the best agreement is obtained with a Navier–Stokes computational fluid dynamics computation, which assumes a no-slip isothermal wall boundary condition; good agreement is also obtained with a simple shock tube laminar boundary layer model. It is also found that the flow developing within the microchannel is highly dependent on conditions at the microchannel entrance, which control the mass flux entering into the device. Regardless of the micrometre dimensions of the present facility, shock wave propagation in a microchannel of that scale exhibits a behaviour similar to that observed in large-scale facilities operated at low pressures, and the shock attenuation can be explained in terms of accepted laminar boundary models.