20141203

Physics presentation: heat transfer applications

Let's now shift gears and preview the various heat transfer phenomena you will be investigating during the last laboratory of this semester...

A Cooper Cooler™, where beverages are spun while being sprayed with ice water:
"The Cooper Cooler™ chills beverages on demand ninety times faster than a refrigerator, and forty times faster than a freezer. So that means you can chill a bottle of wine in six minutes, and your sodas in one minute... And because it's spinning and not shaking your carbonated beverages, you don't have to worry about them exploding."
If you choose, you can investigate whether these claims are valid with an actual Cooper Cooler™! (Video link: "Cooper Cooler - Rapid Beverage Cooler.")

Or Coffee Joulies™:
"Fresh coffee is often too hot to drink when it's first brewed. This is especially true when you throw it in your insulated travel mug and you head out to work, and you're waiting and you're waiting for it to cool down enough and you carry it around and you can't even drink your coffee..."

"[Coffee Joulies™ are] shaped like giant coffee 'beans' made of stainless steel. You just drop these in your hot coffee, one 'bean' for every four ounces of coffee, and it cools right down to 140° in a few seconds, that's the perfect temperature for drinking. Then the Coffee Joulies™ hold your coffee at that temperature so you can take your time and enjoy it."

"The secret is inside--there's a proprietary substance that's encapsulated inside the steel 'beans' and it's called a phase-change material. This one has a melting temperature of exactly 140°, so when you put it in your hot coffee, it absorbs the heat, cooling all the coffee around it, so it's completely liquid inside the steel 'bean.' Then the phase-change material slowly releases that heat back into the coffee until it becomes a solid again. And in our tests, they kept coffee at 140° for two full hours..."
Again, in laboratory, you can choose to investigate these claims--however, not with actual Coffee Joulies™ (they're somewhat pricey), but with packets containing the same phase-change substance (food-grade sodium acetate). (Video link: "Coffee Temperature Regulator.")

And reflective "space blankets," used in emergency survival situations to retain body warmth, compared to plain heavy-duty garbage bags:
"I'm a big fan of using heavy-duty garbage bags for temporary survival... But as your sole survival device, you just need to know that an emergency space blanket like this works really well...[but only] in space, which where they're designed to be used, where radiative heat loss is the primary means of heat loss."
You can also choose to investigate whether a garbage bag or a space blanket would be more effective for emergency conditions...here on Earth. (Video link: "The Problems With Space Blankets.")

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