Replacement Particle Image Velocimetry (PIV) Laser

正确地描述流体流动需要对整个流场进行精确的速度测量。当我们同时获得空间中许多点的流动信息时，就能更好地理解流场的物理性质。计算机技术和数字成像技术的快速发展促进了粒子图像测速技术的发展。为了执行PIV，在流中播种微小颗粒（如烟雾或雾），并使用强大的激光照射。然后，使用高速摄像机捕获两个连续的流图像，并使用复杂粒子跟踪算法进行比较。最终的结果是整个流场的速度矢量的完整阵列。******UNB目前有一个LaVision立体PIV系统，工作状态良好，但照亮流的激光已经老旧，不再正常工作。我们激光器的制造商已经被出售，不再生产PIV激光器。鉴于修复当前激光器的成本与购买新激光器的成本相当，并且鉴于激光器的一些部件不再生产，我们认为最好的方法是购买新的替换激光器，以便我们可以再次执行PIV。因此，我们要求资金用于替换功率与旧激光器相当的激光器。替换激光器具有防震设计，不需要常规光束对准；这意味着该激光器比目前的激光器更安全，因为激光器的光室不需要定期打开。这种防震设计特别适合于我们对加速流动的研究。**

Properly characterizing fluid flows requires accurate velocity measurements over the full flow field. A better understanding of the physics of the flow field is gained when we have simultaneous information about the flow at many points in space. Rapid advances in computing and digital imaging have facilitated the development of the Particle Image Velocimetry (PIV) measurement technique. To perform PIV, a flow is seeded with tiny particles (like smoke or mist) and illuminated using a powerful laser. Then, two successive images of the flow are captured using high speed cameras and compared using complex particle tracking algorithms. The end result is a full array of velocity vectors throughout the flow field.******UNB currently has a LaVision stereoscopic PIV system that is in good working order but the laser that illuminates the flow is old and no longer working properly. The manufacturer of our laser has been sold and are no longer making PIV lasers. Given that the cost of repairing the current laser is comparable to the cost of buying a new laser and given that some components of the laser are no longer being made, we believe that the best way forward is to purchase a new replacement laser so that we can again perform PIV. Thus, we are requesting funds for a replacement laser of comparable power to the old laser. The replacement laser has a shockproof design that does not require regular beam alignment; this means that the laser is safer to use than the current laser as the optical chamber of the laser does not need to be regularly opened. The shockproof design is particular suited for our research on accelerating flows. **