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Posts Tagged ‘drink’

Finally, Science is Doing Something Useful!

April 5, 2011 1 comment

Photo Credit: Aaron Logan

I love coffee. It has lots of flavour nuance (yes, I actually said nuance) and my brain loves stimulants.

But here’s the problem. I come into work in the morning, and I get a coffee. It is too hot to drink at first, so I let it sit for a few minutes.

However, after reading a few emails I get distracted and forget about my poor coffee. By the time I remember it, which is usually about an hour later, it is far too cold.

So I take it to the microwave to heat it up. However, it gets too hot, so I have to let it sit for a few minutes.

And the cycle goes on. It is definitely one of our #firstworldproblems, but it annoys me nonetheless.

But behold! The Coffee Temperature Regulating Thing-a-ma-jig!

The Coffee Joulie

Actually they are called Coffee Joulies, and they even have a Kickstarter page to raise some money to get the business up and running.

So how do they actually work? Each stainless steel “joulie” contains a material which melts at 140 degrees Fahrenheit (60 degrees Celsius). If the coffee is hotter than this, the material absorbs thermal energy by undergoing a phase change (melting). This helps cool the coffee down faster. Once the temperature of the coffee dips below 140, the material remains slightly hotter than that until it solidifies, which keeps the coffee hotter, longer.

And no, I am in no way affiliated with these two guys who started this company, and I have no financial interest in the product. I just think it is an interesting solution to a common problem, and the solution is elegant in its simplicity.

The Physics of Coffee Rings

November 24, 2010 Leave a comment

In keeping with the abstract on the physics of jump rope, the 63rd meeting of the American Physical Society has yielded yet another fascinating study.

63rd Annual Meeting of the APS Division of Fluid Dynamics

Volume 55, Number 16 

Abstract: RU.00007 : Coffee ring deposition in bands

Authors:

  Shreyas Mandre
    (Brown University)

  Ning Wu
    (Colorado School of Mines)

  Joanna Aizenberg
    (Harvard University)

  Lakshminarayanan Mahadevan
    (Harvard University)

Microscopic particles suspended in a liquid are transported and deposited at a contact line, as the contact line recedes due to evaporation. A particle layer of uniform thickness is deposited if the particle concentration is above a threshold; below this threshold the deposit forms periodic bands oriented parallel to the contact line. We present a model for the formation of these bands based on evaporation leading to the breakup of the thin liquid film near the contact line. The threshold results from a competition between evaporation speed and deposition speed. Using this model, we predict the thickness and length of the bands, making the control of patterned deposition possible.

[My comments: The authors used glass particles in a liquid to mathematically model how rings form. They can make these predictions using parameters such as evaporation rate and surface tension of the liquid. Aside from just being interesting, this study may have some practical implications for working at small scales.

Controlling the ring deposition process would be useful for creating such things as new microphysics tools operating at a scale where pliers or other traditional tools for moving particles cannot operate,” notes Mandre. (From Physorg.com)]