Study on High-Pressure Compression Waves in Powdered or Porous Material

粉末或多孔材料中高压压缩波的研究

• 批准号: 01550043
• 负责人: NAGAYAMA Kunihito
• 金额: $ 1.28万
• 依托单位: Kyushu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01550043/
• 关键词: Compression (Shock) Wave; Powder; Gas-Solid Two Phase System

We have constructed a high-pressure gas gun to produce the precisely reproducible and controllable plane shock wave in condensed media including porous materials. By adopting the high-pressure gas powered gun, it is possible to measure the shock wave phenomena accurately by various optical techniques. It has a bore of 20 mm diameter, a launch tube of 1 m length, and an observation chamber of 320 liter. The volume of high-pressure chamber is about 16 liter.First, we have tried to develop a projectile velocity measuring system. A He-Ne laser beam has been introduced into the observation chamber through one of the window, crossing three small through holes of the extension tube of the launcher, led to photodiodes outside. The outputs via amplifier have been used for the velocity measurement and the input for the trigger pulse generator.Preliminary runs have been made by changing the parameters like gas pressure (3 - 30 atm), projectile mass (4.5 - 10.7 g), etc. Under the conditions of 30 … More atm gas pressure, and 4.5 g of projectile mass, the measured velocity is equal to 360 m/s. It is found that projectile velocity is roughly proportional to the logarithm of gas pressure with the same values of other parameters. Reproducibility of projectile velocity upon various parameters has been found to be very good.A new optical pin has been developed, having possibility of detecting elastic waves. Two plastic optic fibers were fused together at an angle over 45 degrees. Light beam incident on one fiber end surface is supposed to be totally reflected at the fused surface to output from the other end. Light intensity decrease upon the wave arrival, however, has been found to be non-drastic, probably because the destruction of the fiber surface is not instantaneous at the pressure level of several kilobars generated in our experiments. The pin system is still useful to measure the propagation velocity.This pin method and the electromagnetic gauge method have been used to investigate the compression wave propagation behavior of alumina powder of porosity 0.6. For the projectile velocity of 272 m/s, shock wave velocity, front pressure and the compressed density is estimated to be 571 m/s, 0.185 GPa and 2.4 g/cm^3, respectively. Within the range of pressure in our experiments, the attained density does not reach the crystal density, so that the compaction is incomplete. Less

我们研制了一种高压气炮，用于在多孔材料等凝聚介质中产生可精确再现和可控的平面激波。采用高压气动炮，可以利用各种光学技术对冲击波现象进行精确测量。它有一个直径为20毫米的口径，一个1米长的发射管和一个320升的观测室。高压舱的容积约为16升。首先，我们尝试研制了一套弹丸速度测量系统。He-Ne激光束通过其中一个窗口进入观察室，穿过发射器延长管的三个小通孔，通向外面的光电二极管。通过放大器的输出用于速度测量和触发脉冲发生器的输入，通过改变气体压力（3 - 30 atm）、弹丸质量（4.5 - 10.7 g）等参数进行了初步试验，在30 ...更多信息 大气压和4.5g的射弹质量，测得的速度等于360 m/s。结果表明，在其他参数相同的情况下，弹丸速度与气体压力的对数近似成正比。实验结果表明，弹速对各种参数的再现性都很好，并研制了一种新的光学探针，有可能探测弹性波。两根塑料光纤以超过45度的角度熔合在一起。入射到光纤一端表面的光束被假定为在熔融表面处被全反射以从另一端输出。然而，已经发现波到达时的光强度降低是不剧烈的，这可能是因为在我们的实验中产生的几个压力水平下，纤维表面的破坏不是瞬时的。用这种方法和电磁计法研究了孔隙率为0.6的氧化铝粉末的压缩波传播特性。当弹丸速度为272 m/s时，激波速度、前缘压力和压缩密度分别为571 m/s、0.185 GPa和2.4 g/cm^3。在我们实验的压力范围内，所获得的密度没有达到晶体密度，因此压实不完全。少