NJIT Expert Wins NSF Career Award to Study Fluid-Solid Interaction
Engineers keep deriving new applications from research into what happens when solid objects interact with fluids such as gasses and liquids — it’s useful knowledge for aerospace, energy and healthcare — but new applications in turn require more research, in an endless cycle that may soon skip a few loops because of an NJIT professor’s improvements to the hottest software in his field.
The software is called DualSPHysics. It was developed in the 2010s to simulate fluid flows using particle methods, which considers fluids as theoretical gatherings of tiny particles that move and act on each other. DualSPHysics harnesses the computing industry’s graphical processing hardware, but it lacks parallel processing capabilities and there is little hands-on experimentation to prove its results, said Angelo Tafuni, an NJIT assistant professor in the School of Applied Engineering and Technology.
Tafuni is adding those two elements in a project funded by his National Science Foundation Career award of more than $559,000. Any new code produced will be open-sourced. If similar code already exists, it would likely be unavailable to the academic community, he noted.
“I've always been just fascinated by fluid motion and studying what happens when you have different types of flows [such as] what goes on from a physics standpoint at the molecular level. That's been my broad interest. And the fluid-structure interaction came about when I became a little bit more experienced with studying these phenomena during my research and Ph.D.,” Tafuni explained.
“One of the hardest things to do in fluid mechanics, when you're trying to model a problem, is to figure out the interaction of fluid with a solid boundary like a wall or a wing. It becomes very challenging because you have to establish very accurate boundary conditions. … There are many methods out there that still don't have accurate and robust boundary conditions,” he said.
Challenges and new directions
People have been addressing the problem with computers since the middle of the last century, Tafuni said. Beside adding parallelization, which lets the software solve its problem on multiple machines at a time, there’s also an artificial intelligence aspect. Gennaro Fraccalvieri, an NJIT graduate student pursuing an M.S. in mechanical engineering, is developing AI software to minimize how many computer simulation runs are necessary. That will save time and money, Tafuni said.
The project officially begins in September 2025 and runs for five years. It won’t be easy. “There are several challenges. The project itself is very ambitious because of the different elements that are in there. There's going to be physics, engineering, computer science and also some experimentation. It's not easy to address all these things,” Tafuni observed. “So interdisciplinarity, I would say, is one of the strengths and also weaknesses.”
One specific application driving Tafuni now is his interest in space exploration. He said that in future projects, he’d like to record data about fluid-solid interaction in low-gravity environments such as those on the moon or Mars. To do so, he and associate professor Samuel Lieber already built an unnamed robot that shakes containers of fluids. The robot has six arms so it can move a container in any direction. Tafuni said he’s working toward earning NASA funding that will let him bring the robot onto an airplane flying in parabolic arcs that simulate microgravity.
