Inhalable Particle Behaviors in Laminar Flows Around Triangular and Circular Cylinders

Attention to inhalable particulate matter (PM10) has increased in recent years due to the growing threat of its pollution to public health. Behaviors of individual particles in various flow fields are of great interest, but few results from direct observation/measurement are available. The present work develops an integral image-based scheme consisting of a microscope, a high-speed CCD camera, a view chamber, a mass flow controller, and an image processing package. This system is used to investigate behaviors of inhalable particles in a laminar flow passing a triangular or circular cylinder. Moreover, numerical simulations are conducted and compared with experiments. The particles are found to follow the laminar fluid flow well, but still with small random fluctuations. When the flow is slow, the fluctuations are more obvious.