Miniaturized particle sizer for field application

喷雾和喷嘴广泛应用于各种行业，包括涂层、冷却、清洁、喷漆和加油。在所有这些应用中，喷雾特性影响到工业或农业过程。这些特性包括喷雾液滴的大小、速度和质量分布，其中喷雾液滴的大小是最重要的特性。液滴的大小决定了液体的喷射量，因此，喷雾不当可能会对工艺造成重大损害。它会产生过多的有价值的物质，因为操作不当的喷雾会影响水和电的消耗，并会降低成品的质量。最常见的非侵入性测量液滴尺寸的方法有：(1)光学粒子计数器(成像)(2)激光衍射仪，(3)激光或相位多普勒测速仪。图像处理缺乏准确性，特别是在难以实现光学访问的情况下；然而，它可以用于表征各种液体喷雾，并且相对简单和低成本。另一方面，基于激光的系统在短时间内提供了大量准确的数据，但其复杂，安装和应用非常耗时。它们的使用需要实验室环境和专门的培训。它们也是非常昂贵的设备，因此，它们主要用于研究目的，在行业中很少用作表征喷雾大小的工具。通常的方案是将喷嘴送到研究机构进行测试。 目前，还没有一种简单快速地测量液滴大小和速度的方法。操作员在更换喷嘴之前依靠目测或经验确定的变化。然而，喷嘴早在被检测到之前就已经有缺陷了，这是有据可查的。解决这一问题的解决方案将使许多行业以及学术界和研究中心受益，这些行业和研究中心无法获得昂贵的测试设备和设施。这项工作将开发一种廉价、准确的颗粒测量装置，能够满足这些需求。

Sprays and nozzles are used in a wide range of industries with a variety of applications that include coating, cooling, cleaning, painting and fueling. In all these applications, the spray characteristics impacts an industrial or agricultural process. The characteristics include the spray droplet size, velocity and mass distribution with spray droplet size being the most important characteristics. Droplet size determines the amount of liquid sprayed as a result improper spray can cause significant damage to the process. It can produce excessive amount of valuable material as a poorly operating spray affects the consumption of water and electricity and can decrease the quality of the finished product. The most common methods of non-intrusive measurement of droplet size are: (1) Optical Particle Counter (imaging) (2) laser diffraction analyzer, and (3) Laser or Phase Doppler Velocimetry. Image processing lacks accuracy especially where optical access is difficult to achieve; however, it can be used to characterize a variety of liquid sprays and is relatively simple and low cost. Laser based systems, on the other hand, provide a large amount of accurate data in a short time, however, they are complex and their installation and application is very time consuming. Their use requires a lab environment and specialized training. They are also very expensive devices, therefore, they are mainly used for research purposes and hardly used in the industry as a tool to characterize spray size. The usual protocol is to send the nozzle to a research facility for testing. Currently, there are no method of measuring droplet sizes and velocities in a simple and rapid fashion. Operators rely on visual tests or experientially determined changes before changing a nozzle. However, it is well-documented that a nozzle is defective long before it is detectable. A solution which addresses this would benefit a wide range of industries as well as academia and research centers which do not have access to expensive testing equipment and facility. This work will develop an inexpensive and accurate particle sizing device capable of meeting these needs.