Engineers have relied on water’s capacity to store and transfer energy for centuries: putting it to work driving steam locomotives and turning power plant turbines. Baristas also rely on water as a solvent to extract flavorful compounds when brewing coffee and as hot pressurized steam to quickly heat and texture milk. Water can be dangerous and destructive too. Excessive steam pressure can cause a boiler to burst explosively and freezing water may rupture pipes or espresso machine components. For these reasons, understanding water’s behavior is important for the coffee technician.

Through the medium of thermometers, Michael Teahan reminds us to be open to new ideas, even when we’re fully convinced of what we know…

“There’s no need to get a degree in engineering to degunk a clogged group or replace a pump, but in both cases you’re working to solve a problem that encompasses pressure and flow, the two bedrock concepts in fluid mechanics.”

Arno Holschuh explores Pressure and Flow.