Feeling Supersonic: Researcher Helps Make Planes, Rockets Go Faster
Nick Parziale lives for the supersonic.

Parziale, a Stevens professor of mechanical engineering, studies the ways rockets, spacecraft, planes and other objects soar through the atmosphere and space at more than five times the speed of sound (Mach 5).
He’s particularly focused on measuring the flow of gases around those vehicles as they travel. The thin gas layer around a vehicle, known as a boundary layer, changes from a well-ordered, laminar state to a turbulent, chaotic state as a vehicle travels. Knowing those states’ transition point is important for designers, because a craft that creates a more turbulent boundary layer creates higher drag and more heat transfer, requiring more onboard power and more thermal protection from the friction of traveling at high speeds through atmosphere.
The key, Parziale explains, is measuring those gas flows without disturbing the flow itself as it’s being measured — and he develops various optical-based sensing methods to do so, such as krypton tagging velocimetry, or KTV. The technique uses krypton atoms and the excitation of atoms to image the flow field in flight.
Partners and agencies including the Air Force Office of Scientific Research (AFOSR) and the Office of Naval Research (ONR) have supported Parziale’s work, building Stevens’ lab laser and camera systems in the process.
That’s not all Parziale does. He also performs research to help design reactor plants that could convert biomass to bio-oils via a process known as fast pyrolysis — cutting down on carbon emissions in the process. And he assists a broader Stevens effort to derive nitrogen-based fuels from wastewater streams.
“[There is an] energy in the laboratory when you have the aha! moment,” he says of his experience teaching and performing research at Stevens. “It’s great to share the experience with students where you finally figure out how to perform an experiment or calculation. It’s really fun to say, ‘we did something really interesting today; folks in our research community are going to be really interested in hearing about this."