Are YOU smarter than a freshman? Try your hand at this freshman engineering problem and find out for yourself.
Question: Albert Einstein had an abdominal aortic aneurysm in 1948. It was
surgically treated by wrapping the abdominal aorta in cellophane to induce fibrosis and restrict the growth of the aneurysm.
That repair lasted approximately
seven years before the aneurysm ruptured. Today, these issues
are treated with endovascular grafts, or tubes placed inside
the aorta. They are made from a woven polymer fabric. The goal is to induce local blood clotting and allow new artery walls to
grow on the surface of the fabric. Which of the following two
materials would be better suited to this application, Teflon (PTFE,
Polytetrafluoroethylene) or Dacron (PET, Polyethylene terephthalate)?
Solution: As the goal is to induce clotting, Dacron would be the preferred choice. PET is typically more prone to forming clots than PTFE, due to higher surface energy. 18 Auburn Engineering
It’s my job
by Jim Killian
Charlie Ping, ’04 mechanical engineering Project manager, IndyCar race operations Pratt & Miller New Hudson, Mich. Typical day . . . making the partnership between Pratt & Miller and
Chevrolet work for all of the race teams running our engines. Chevrolet has tasked us to characterize the IndyCar vehicle and support Chevrolet powered teams in vehicle dynamics and simulation. When I get to the track, I coordinate with the trackside engineers in the race paddock, and we look at software, vehicle dynamics, testing and development issues. Every team has an embedded engineer, and each team has different needs, even though they are running essentially the same engine and chassis.
Engineering challenge . . . every team is trying hard to get a competitive advantage, and there’s always a lot of backchannel talk in the pits about who is doing what with the engine and chassis. Even little changes in your setup can make a lot of difference in track times . . . like when I hear a driver say, “I don’t understand this new tire!“ You know, it could be the track surface, the downforce on the racecar, the tire compound, or the temperature. The challenge is that the interaction of many factors comprises total vehicle performance and it is sometimes difficult to identify which areas are the most performance sensitive. Living the life . . . in this kind of job, it can’t just be a job. It’s good if it is your hobby too . . . and your life. The travel schedule is demanding. Last year I took more than 1OO flights testing the new car and engine at different tracks, because they all treat the car differently. The track at Sebring is not like the one at Texas, and Texas is not like the oval at Fontana, it’s that simple. We don’t race in the snow, so racing generally follows good weather . . . which also means that I am not in Michigan often in the summer, which is the nicest time of year in the Midwest . . . sometimes I get tired, but I don’t really get tired of being at the track. Geek moment . . . don‘t ask me how smart you have to be for this job. I can feel pretty stupid around here, if you want an honest answer. In this business, you can get humbled really quick, because a vehicle and its interaction with the circuit is such a complex problem . . . you have to be analytical . . . and you have to pay your dues. Sense of pride . . . I have such a deep appreciation of technology and engineering, and I love what I call ‘pure engineering development‘ . . . the kind that I am exposed to during the off-season. It gets a little crazier at the track because the emphasis is so much on immediate results. It has to be – that‘s why we have the jobs we have. My Auburn Engineering . . . I was lucky to have some great experiences at Auburn with the Formula SAE team including one of its best-ever finishes in collegiate competition . . . that allowed me to jump into this difficult business and hold my own . . . and I‘m having a blast.