As a fluid dynamicist and mechanical engineer at the National Institute of Standards and Technology (NIST), I’ve devoted much of my career to helping others see things that are often difficult to detect. I’ve shown the complex flow of air that occurs when a dog sniffs. I’ve helped develop ways to detect drugs and explosives by heating them into a vapor. I’ve explored how drug residue can contaminate crime labs. I’ve even shown how to screen shoes for explosives.

Most of these examples fit into a common theme: detecting drugs and explosives through the flow of fluids that are usually invisible. When I’m in the laboratory, I use a number of advanced fluid flow-visualization tools to help better understand and improve our ability to detect illicit drugs and explosives on surfaces, on people, and in the environment.

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