With nearly 10 million YouTube subscribers, the Slow Mo Guys (Gavin Free and Daniel Gruchy) are Internet superstars, always on the lookout for interesting things to film in slow motion. That's why this Purdue tweet of a hypergolic explosion caught their attention. They brought their time-warping cameras to Purdue's campus and showed us just how amazing engineering can be at 28,000 frames per second.
World's Largest Drum
What better way to start their Purdue visit than by having a go at the World's Largest Drum? And what better way to showcase this amazing musical instrument than by filling it with confetti and ping-pong balls? In the behind-the-scenes, we learn what it takes to keep this giant percussion instrument rolling -- and from professors Stuart Bolton and Steven Wereley, learn the mechanical engineering behind why the confetti and ping-pong balls did what they did.
In its liquid form, copper retains its reddish color and looks super cool when being poured. Downside: copper melts at 1,000 degrees Celsius. Looks like we need an expert! Kevin Trumble of the School of Materials Engineering melts down the copper at the Purdue Center for Metal Casting Research with an induction furnace, which creates very high temperatures with a massive amount of electrical current (thus the high-pitched noise in the video). These liquid metals are no joke, which is why this video required extensive safety measures -- but the visual results speak for themselves!
Zucrow Labs is the largest academic propulsion lab in the world, testing rockets and jet engines. Visiting Zucrow is like being in a candy store of explosions! And here's the granddaddy of booms: a 20-foot long Sandia combustion tube, spitting flames out at 4,000 miles an hour. Built by students of Sally Bane of the School of Aeronautics and Astronautics, it's designed to test the moment when a subsonic flame becomes a supersonic explosion (called deflagration-to-detonation transition). But as Dan says in the behind-the-scenes video, the Slow Mo Guys are just interested in blowing stuff up!
Steel Rod / Hydraulic Press
Steel rebar isn't exactly known for its speed... except when you pull it apart with 157,000 pounds of force! Under those forces, even a 1.5 inch-thick steel rod will snap like a twig, which is why the Slow Mo Guys filmed it at 148,000 frames per second. Then they moved on to a hydraulic press, which measures the compressive strength of materials (obviously a deck of cards is no match for 90,000 pounds of force). Both machines are part of Shirley Dyke's Civil Engineering research at Bowen Lab, a 66,000 square-foot facility where they test the strength of materials that go into structures, buildings, and bridges.
These rockets may look like cardboard and plywood, but inside they pack a powerful enough punch to go 1,000 feet in the air in just seconds. They were built by Purdue SEDS (Students for the Exploration and Development of Space), who also organize things like astronaut reunions and orbital rockoons. They furnished this rocket with a G model engine and a sparker to make it look cool -- and boy does it deliver. In fact, the second rocket got carried away by parachute to Slayter Hill, and stuck in a tree 20 feet up (don't worry, we got it down!)