Well, since your game isn't old enough for the Elder professors to have died off, check out the topic 6 or 7 down from this one, Britechester Residents and Lot Info. When you get down to the homeless premade sims, the professors are there, so you know their names and what they look like. Serena Bhamra, I run into in the Foxbury Commons pretty often. And I'm pretty sure, if it's one of YOUR professors, they will be tagged above their name. Also, if it's one of your professors, you'll have a couple of special interactions to ask them about your grades.
Also, if there's an Adult or Elder hanging out in the Commons, pretty good chance it's one of the professors. Not guaranteed though, townies from all over will make appearances. They WON'T be tending the cafeteria station though. And if you know their name from elsewhere, not a professor- the townies from Island Living turn up a LOT on campus.
Lol and my avatar, that's sim me. I didn't put a lot of time into getting his face just right, so he's basically one of the stock premade faces, a Maxis goatee, I think the hair is CC but not a whole lot different from a Maxis one. One of the Maxis glasses turned out to be pretty darn close to my real ones. So the game kicking out a sim me randomly wouldn't be terribly surprising lol.