As a very non-engineering, can't-do-math-in-my-head kind of person, I often find my eyes glassing over in any attempt to read most CFD articles. I'm sure it's all very fascinating, but really, how will a dredge ball joint with improved flow, or the proper cooling of a multimode phonon laser have much (if any) immediate impact on my life? Unless the aforementioned ball joint is yet another part on the ever-growing list of recalled parts for my Saturn, I'm not seeing it.
Then I ran across an article the other day that made me, ahem... perk up. CFD was used to simulate roasting coffee beans! Coffee is something I know AND care about. But why would CFD be needed for something as "non-techie" as roasting beans? Like everything else under the sun, it comes down to plain ol' chemistry. The final flavor profile of the bean will vary widely based on temperature and roast time.
Gone are the days of tin-tasting percolator brew and (shudder) Sanka instant decaffeinated coffee. There's now a gourmet java shop on every street corner and multiple ones throughout most modern malls and airports. It's no longer a matter of choosing between regular or decaf...
I'll take a grande, upside-down, 1% organic milk, triple-shot, double-pump, sugar-free vanilla caramel frappe-latte with extra foam and a hazelnut undertow.
Coffee is a $30 billion a year industry... in the USA alone! Throw in the price of coffee (which gets higher by the day) and the influx of "coffee connoisseurs", it's best to get it right the first time!
In an article written for Engineering.com, CFD specialists Professor Luca Montorsi from the University of Modena and Reggio Emilia explains how he helped Petroncini, a manufacturer of coffee roasters, find the best way to roast a half ton of coffee beans in 15 minutes. The simulation includes interactions between two models that simulate the airflow (a turbulent k-ε model) and the beans (discrete element model - DEM).
The results: the ability to see the relationship between the mass flow rate, maximum temperature and heat distribution among the particles (beans). They also found that the complexity of the blade shape and the speed of the rotor affects the mixing of the beans more than mass flow rate. So based on the bean variety, moisture content, and the desired flavor profile, using CFD makes it easy to determine the best roasting time and temperature for a cup of joe that's "good to the last drop".
To learn more about the specifics of the simulation, read the full article here.