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Looking back over my old work I have discovered some papers I wrote when I took part in the Steorn discussion forums. I think they may be of interest here on this forum. Of particular interest is something I learned about during my professional career associated with military hardware, and in particular guided weapons. Some guided weapons are designed to explode on impact with a hard target, and I learned about experiments to investigate the optimum positions to place the impact sensors.
The study of forces with very fast rise times is a specialist subject not generally taught to electromagnetic engineers. It is mainly of interest to scientists involved with hypervelocity impacts or detonation waves. The important thing to realize is that the sudden application of a force at one point on a body does not immediately give rise to that force being available at another point on the body. This is particularly noticeable in high-speed impacts. There is a time delay between the sudden application of force on the nose of the missile and its presence at any position along the missile structure. During this time a stress wave is propagating through the material at “particle velocity”. Particle velocity is not the same as acoustic velocity. Particle velocity varies with stress, the plot of this velocity against stress is known as the Hugoniot for the material. In the case of a missile hitting a target, if the missile is traveling at a velocity greater then the particle velocity the front end of the missile gets crushed before the back end knows anything has hit it.
I think this aspect of time delay between the application of a force on one end of a structure and its appearance at the other end is something worth investigating, as it is a route to non-reciprocity and possible to OU. To start the ball rolling I attach one of my papers written 10 years ago. I also attach some examples of the Hugoniot for aluminum obtained from Google searches (I can't remember which papers these came from) to illustrate the relatively low values of particle velocity.
Smudge
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Topic: Particle velocity in materials, a route to OU? (Read 3250 times)
