URI mechanical engineering professor simulates bomb blasts to study how things break apart

URI Professor Arun Shukla helps military create bomb-resistant materials

KINGSTON, R.I., Nov. 29, 2016—How much force does it take to shatter a Humvee, a soldier’s body armor, or a submarine?

In his cavernous laboratory at the University of Rhode Island, Arun Shukla—the Simon Ostrach Professor of Mechanical Engineering at URI—is finding answers to those questions and more as he studies how and why things break apart. His research is taking on greater importance and relevance during these turbulent times.

A world leader in fracture and experimental mechanics, Shukla has been working with the American government since the early 1980s to create stronger materials that can withstand damage from explosions and other catastrophic events. Most recently, he has conducted experiments for the U.S. Department of Homeland Security and the U.S. Department of Defense.

“Our objective is to find better ways to protect soldiers and civilians—and make our infrastructure stronger and more durable,’’ says Shukla. “As the world becomes more violent, this type of research is crucial to make us safer.’’

In his laboratory in the Kirk Center for Advanced Technology on the Kingston campus, he and his students—undergraduates and graduates—simulate bomb blasts and other explosions in two devices: a huge pressurized steel water capsule and a 33-foot aluminum shock tube.

With that equipment he creates a controlled explosive environment so he can test how materials stand up to blasts—and also ensure that his students are doing safe experiments.

The shock tube simulates the rush of high-pressure gases from an exploding bomb to test materials. Helium is pumped into the tube to break a covering, then the gases race down the tube at three to four times the speed of sound and hit the material at the end.

Estefany Mejia and Chris Salazar, undergraduates studying mechanical engineering at URI, examine a shock tube with Arun Shukla, the Simon Ostrach Professor of Mechanical Engineering at the University. URI photo by Nora Lewis
Estefany Mejia and Chris Salazar, undergraduates studying mechanical engineering at URI, examine a shock tube with Arun Shukla, the Simon Ostrach Professor of Mechanical Engineering at the University. URI photo by Nora Lewis

The 7-foot-tall, 1,800-gallon water capsule simulates the pressure deep in the ocean to measure how underwater shock waves and explosions affect materials and structures at that depth.

Both devices evaluate different materials and structures. With the shock tube, Shukla examined how blasts damage glass windows and buildings. That study was for Homeland Security. Using the tank, he is looking at how structures in submarines collapse from water pressure and blasts. The study is being done for the U.S. Navy.

Shukla built the shock tube with Carl-Ernst Rousseau, now chair of Mechanical, Industrial and Systems Engineering at URI. Shukla designed the water capsule, which was built in Virginia and shipped to URI three years ago. Both devices loom large in Shukla’s Dynamic Photomechanics Laboratory, where the equipment hums steadily as it readies for the experiments.

“This research equipment is unique and highly suited for studying catastrophic events,’’ says Shukla. “URI’s engineering college is doing cutting-edge research that is highly valuable for the state, the country and the world.’’

His students agree: “I feel lucky to be studying under Dr. Shukla,’’ says Helio Matos, of Fall River, Mass., a doctoral student in mechanical engineering whose dissertation involves experiments he’s done with the water capsule. “There is no better place in the world to do the kind of research we do, especially underwater structure analysis. The research is far-reaching and rewarding.’’

The tests often last less than one millisecond, so three high-speed cameras that can take photos ranging from 30,000 to 200 million frames per second record the action. “This allows us to see the event, as it evolves, in slow motion,’’ says Shukla.

His team examines the photos to understand how damage happens and how it can be prevented. Sensors on the shock tube and tank also pick up high pressures generated by the blast. Those results are analyzed on computers.

His list of sponsors is long—and impressive. Besides Homeland Security and the U.S. Office of Naval Research, he has collaborated with the U.S. Air Force Office of Scientific Research, the Naval Undersea Warfare Center in Newport, the National Science Foundation, the U.S. Army Research Office, and the Rhode Island Department of Transportation.

For the U.S. Air Force, he examined how energy from explosions travels through the ground in a quest to figure out how a blast affects underground silos. For several years, he’s been studying how metals in supersonic jet planes fare under extreme temperatures and pressures.

“We’re trying to create a metal that will allow planes to fly extremely fast,’’ says Shukla. “The challenge is that metals get very hot and melt under extremely high velocities.’’

Growing up in Lucknow, a city in northern India, Shukla enjoyed tinkering with mechanical toys as a child, an interest that took him to the Indian Institute of Technology, the top engineering school in the country at the time. After graduating in 1976 with a bachelor’s degree in mechanical engineering, he travelled to the United States to study at the University of Maryland in College Park, where he earned his doctorate, also in mechanical engineering.

He joined URI in 1981 as an assistant professor and became a full professor in 1988. In 2000, he was appointed to his current position. Over the years, he’s written and edited 10 books, authored more than 350 papers and won numerous awards. In 2011, he was the Clark B. Millikan Visiting Professor at the California Institute of Technology. He was elected to the Russian Academy of Engineering in 2015, and the European Academy of Sciences and Arts in 2011. He lives in Wakefield with his family.

“I feel privileged to be at URI,’’ Shukla says. “I thank the state and the University for all the support they’ve given me over the years. I plan to continue my important research to make the world a better place.’’