Miniaturized particle sizer for field application

喷雾器和喷嘴广泛应用于各种行业，包括涂层，冷却，清洁，油漆和加油。在所有这些应用中，喷雾特性影响工业或农业过程。其特征包括喷雾液滴大小、速度和质量分布，其中喷雾液滴大小是最重要的特征。液滴的大小决定了喷射液体的量，因此喷射不当会对工艺造成重大损害。它会产生过多的有价值的材料，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。最常用的非侵入式液滴尺寸测量方法有：(1)光学粒子计数器（成像）；(2)激光衍射分析仪；(3)激光或相位多普勒测速法。图像处理缺乏精度，特别是在光学访问难以实现的情况下；然而，它可以用来表征各种液体喷雾剂，并且相对简单，成本低。另一方面，基于激光的系统可以在短时间内提供大量准确的数据，但是，它们非常复杂，并且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，在工业中很少用作表征喷雾尺寸的工具。通常的方案是将喷嘴送到研究机构进行测试。

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.