Visit Portsmouth, New Hampshire, about 20 minutes away from campus, and head towards the coast. Go to the northeast corner of downtown, towards Prescott Park, and you will see the Memorial Bridge crossing the Piscataqua River, joining New Hampshire and Maine. That bridge has a variety of sensors and equipment on it, monitoring variables about the bridge and the water flowing past it. Part of this equipment is a University of New Hampshire (UNH)- developed turbine—similar to the iconic wind turbine but with underwater blades.
This turbine was tested on campus in the Jere A. Chase Ocean Engineering Laboratory, as part of the Living Bridge Project. The project is one of many that take place in this “deceiving” looking building, as Dr. Martin Wosnik termed it. Wosnik is an associate professor within the College of Engineering and Physical Sciences (CEPS), and has been one of the lead investigators on the Living Bridge Project.
One of the most striking parts of the building is the high bay, a cavernous space filled with a variety of equipment for projects related ocean and mechanical engineering, seafloor mapping and more. Two water-filled tanks take up much of the floor space, along with smaller areas for students to work on independent projects, outreach space, small boats and a large buoy.
“We call it the engineering tank, and that tank is used for evaluating autonomous surface vehicles, it’s used for evaluating underwater vehicles, remotely operated vehicles, it’s also used for evaluating acoustic transducers. And it’s used for a number of other scientific studies,” she said of the wider of the two water tanks. The engineering tank, 20 feet deep, was home to some of the activities at Ocean Discovery Day, the annual event that shares UNH’s ocean research with the public.
The high bay and the building itself serve many: CEPS research and students, the Center for Coastal and Oceanographic Mapping and the Joint Hydrographic Center, working alongside the National Oceanographic and Atmospheric Administration (NOAA). External companies also use the facilities, said Dr. Diane Foster, a professor in and the director of the School of Marine Science and Ocean Engineering.
“This has historically been a place where an on-campus facility for testing and evaluating systems and processes relative to our oceans,” Foster said.
The Chase lab is one of the younger buildings on campus. Wosnik named three professors, who were instrumental in pushing forward the construction of the Chase lab.
“They got the core part of this building built back in the early 1990s” Wosnik said. “That was just the high bay and [some of] the offices…The Center for Coastal and Ocean Mapping has added twice to the building.”
One of those additions was as recent as 2017, as Foster described. The additions added a number of offices, laboratories, a classroom, and spaces for constructing and developing engineering structures.
This past fall, “a full-scale flume” tunnel was placed alongside the longer 120-foot tank. This tunnel, stretching much of the length of the tank, has both water and sediment in it, allowing study of waves and their impact on sediment—their impact on the seafloor, on beaches. It looks like an extended version of wave models that can be found in museums and aquariums.
The tank this flume is next to, the wave/tow tank, is a tank Wosnik uses often. Objects are often towed along the length of tank, allowing researchers to understand the waves created by an object and waves it may interact with. Both this and other tanks are often an intermediate step in developing equipment for use in the field—i.e., at Memorial Bridge in Portsmouth.
“We actually built a scale version of the bridge pier, and we towed the bridge through the water,” Wosnik said of the Living Bridge project. He also used the tank to tow a turbine. The current iteration of this turbine deployed underneath the bridge “produces about much power as two households need overall, or as we like to say, there’s enough power to charge all the iPhones in Portsmouth,” he said, acknowledging that the project was rather time- and stress-intensive over its many years.
Between the tow and the engineering tanks is a small, concrete cubicle-like area, where some of the smaller seafloor mapping boats are worked on. KG Fairbarn, a research technician, is part of the autonomous surface vehicles (ASV) group. He works on four such boats, which are remotely controlled and map the seafloor and sediment beneath areas they pass over.
The primary vessel Fairbarn and his colleagues work with went on two missions, or tasks, in 2019. The first was freshwater: “We were in Lake Huron looking for shipwrecks out there, surveying the Thunderbay National Marine Sanctuary,” Fairbarn said. The second searched the waters by Nikuaroro, a small island nearly in the middle of the Pacific between Australia and South America. This mission was focused on finding the remains of Amelia Earhart’s last flight, though was ultimately unsuccessful.
Much of Fairbarn’s and his colleagues’ work involves refining the autonomous system of the vessels.
“Being that it’s an autonomous boat and nobody’s on here, we’re trying to make it easier for operators to run the boat,” he said.
These operators are always in contact with a boat, working out of a trailer that travels along with a vessel.
“Nothing’s truly autonomous. Nobody’s created a truly autonomous system. There’s always a human in the loop, now, for safety reasons… Our boat’s not smart enough yet to follow the rules of the road that all boats out there are supposed to follow,” Fairbarn said.
Outside of the high bay are more laboratories, including Wosnik’s, filled with equipment and tools he’s needed in his research. This includes a not-yet-used chainsaw—a fallen tree had gotten caught in the turbine under Memorial Bridge, and it almost needed to be cut apart.
Dominating some of the floor plan of his lab is a cavitation tunnel, about six feet high and 10 feet long, composed of much smaller-diameter long tubes. The tunnel pushes water through its system, creating cavitation.
“Cavitation is just the word for changing the phase of water from liquid to gas,” Wosnick explained. “Basically, you’re boiling water at room temperature if the temperature gets too low. If you have water flowing past, [objects like] hydrofoils, propellers, turbines, really really fast, you actually change phase.”
A phase change is when elements change the form they appear in, like liquid water freezing to ice. Studying this gives Wosnik insight on how well a turbine is performing.
All these resources provided in the Chase building have been beneficial for CEPS and the university, as research has flourished since the construction of the building, according to Foster. UNH offers a minor, major, and both master’s and Ph.D. programs in ocean engineering. The graduate program is over 20 years old, Foster said.
The facility isn’t perfect, though, according to Wosnik.
“Ideally I would like to blow out the back wall and build this tank five times as long. But that would make it much more costly to operate…It’s just nice to have towing tanks that are really really long. I’m happy with what I have. I think when you look around the country, and see what labs of this kind have available, I think we have an outstanding array of facilities, and I’m really really happy with it,” Wosnik said.
The high bay is open weekdays, and students are able to walk around the facility. Foster recommends the ocean engineering minor for students interested in working in the building. For students interested in Wosnik’s work, he asks that the student comes from an engineering background, and that “you have an interest in fluid dynamics, renewable energy and not be afraid to get wet.”