A Guru of Wiffle Ball? Meet Professor Jenn Rossmann

Professor Jenn Rossmann

Jenn Rossmann is living a double life: When she’s not studying fluid dynamics, she’s writing fiction.

“I’m an engineer who likes words,” she says, noting that most of her colleagues have interests outside their field.

An assistant professor of mechanical engineering, Rossmann completed a minor in creative writing at University of California Berkeley, where she also received a Ph.D. studying the physics of blood flow. She has published several short stories, a textbook, and is working on her fourth novel, which is set in Silicon Valley. But she doesn’t reserve writing for home or personal pleasure. She also uses it in the classroom by encouraging her engineering students to express technical terms in ways the average person can understand.

“I tell them to pretend they’re talking to this guy on the bus,” she says.  “I want them to be able to explain their ideas in writing and then consider how an abstract concept can become real and relevant.”

Take the Wiffle ball, for example.

Rossmann has never played the game, but she knows how to scuff or cut a ball in just the right way so it weaves like a fighter jet across home plate. And that has made her a minor celebrity with competitive players, who send her their doctored spheres for analysis.

“We try and figure out what the scuffing and knifing actually does to the trajectory of the ball,” says Rossmann, who along with a former Lafayette student published a study on Wiffle ball aerodynamics in the American Journal of Physics.  That led to an appearance in Yard Work, a documentary that offers an inside look into the wacky world of professional Wiffle Ball and its championship game, played each year in Texas.

Scuffing is illegal in baseball, but in Wiffle ball it’s an essential part of the game because the ball’s eight holes make it difficult to control when hurled between 60 and 80 miles an hour.  A pristine ball gets squirrely at those speeds while a scuffed ball will consistently break away from the holes. That’s why players will use sticks, bricks, sand paper, knives, gravel – just about anything – to disfigure the ball.

“They think they scuffed the ball and it magically changed the pitch,” says Rossmann, who studies the lift and drag forces on banged-up balls in Lafayette’s wind tunnel, which looks like a giant blue mixer in the basement of Acopian Engineering  Center. “But it’s not magic, it’s physics.”

Rossmann teaches students not only how things work, but also the ramifications of that technology on society. For example, in her American studies course, she talks about how the advent of the automobile transformed the country and spurred economic activity by creating a need for roads, gasoline, tires, and other products. In addition, she considers how this change was reflected in art, music, and literature. The road trip became a rite of passage, painters depicted the countryside through a windshield, and novels such as The Great Gatsby and Grapes of Wrath used the Model T to express themes and drive plot.

Writing is a passion, Rossmann says, yet she chose to major in mechanical engineering at Berkeley because it was the most challenging discipline she could bend her mind around.

“The feeling I got from figuring something out was really good,” she says.

It’s a feeling she wants her own students to experience: that moment when a pattern emerges from chaos and the solution becomes clear.

“My job is to help my students get it, to prepare them for the ‘Aha!’” she says. “It’s like Kung Fu. You do the training and when you’re ready a teacher appears.”