Liquid metal diffusion experiments in microgravity—vibrational effects
Liquid metal diffusion experiments in microgravity—vibrational effects
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DOI：
10.1088/0957-0233/16/2/003
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发表时间：
2005-02
影响因子：
2.4
通讯作者：
G. Mathiak;E. Plescher;R. Willnecker
中科院分区：
文献类型：
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作者：
G. Mathiak;E. Plescher;R. Willnecker
熔体中的扩散和对流在大多数涉及液态的工艺过程中起着重要作用。在液体中的许多扩散实验遭受由重力驱动的流动引起的附加传输。因此，不同的研究小组在航天器上进行了微重力条件下的实验。但即使在那里，扩散测量也会受到残余加速度和振动的干扰。为了分析这种额外的运输，在进行零重力飞行机动的飞机内进行了以水为液体的模型实验。由于低重力持续时间短，因此采用了扩散性质量迁移和更快的热迁移之间的类比。毛细管与加速度方向之间的角度在0°和90°之间。对于100 mm的振荡幅度，频率增加到1 Hz导致额外的运输略有增加。1.7 Hz的实验显示了最大50%的额外传输。毛细管和加速度矢量之间的角度的影响在实验误差范围内。
Diffusion and convection in melts play an important role in most technological processes involving the liquid state. Many diffusion experiments in liquids suffer from additional transport induced by gravity-driven flow. Therefore, different research groups performed experiments under microgravity conditions aboard a space vehicle. But even there, diffusion measurements can be disturbed by residual accelerations and vibrations. To analyse this additional transport, model experiments using water as liquid were performed inside an airplane performing zero gravity flight manoeuvres. Because of the short duration of low gravity, the analogy between diffusive mass transport and the faster heat transport was used. The angle between the capillary and the direction of acceleration ranged between 0° and 90°. For an oscillation amplitude of 100 mm, the increase of the frequency up to 1 Hz led to a slight increase of the additional transport. Experiments with 1.7 Hz showed an additional transport of a 50% maximum. The effect of the angle between the capillary and the acceleration vector was within the experimental error limits.