• Posts
  • RSS
  • ◂◂RSS
  • Contact

  • Stirling Engine Pot Stirrer

    August 22nd, 2012
    ideas  [html]
    In chemistry class I really liked the magnetic automatic stirrers we had. The idea is that you put a magnet in the liquid you're heating and then make it spin from below, usually by rotating a drive magnet:
    This would be nice to have for cooking too, but all the culinary stirrers I see are awkward bulky things that you put over your pot and stick stirring utensils down into the liquid. On most gas stoves, including mine, there is some space between the top of the burner and the grate that pots sit on. I want to put a little box there that spins a magnet at the bottom of whatever I'm cooking [1].

    The standard way to spin a magnet like this would be to use electrical power, from the wall or a battery. But either of those is going to be very hard to work with in the high-temperature environment of a stove top. A wind-up stirrer could also work, but while you can get high-temperature spring steel it becomes bendier at higher temperatures which means that if you wind it cold and then put it into the flames it loses a lot of power. [2]

    These also all have the disadvantage of either needing to plug in or be recharged. What if something could run off of the heat energy of the burner? Like a Stirling engine? There's a big temperature difference between the center of the flames and even a few inches away. Let's make that spin our magnet:

    Side:
    
        |~~~~~~~~~~~~~|
        |     pot     |
        |             |
        |  N-magnet-S |    
    
    

    This should be compact, efficient, and useful. It might be kind of expensive; engines are intricate.


    [1] This means using non-ferromagnetic pots, or else the magnet will stick to the pot. Aluminum pots are cheap, however, and lose many (all?) of their disadvantages when combined with automatic stirrers. You also need to be careful not to eat the magnet.

    [2] I haven't done the calculations to determine whether this is prohibitive.

    Comment via: google plus, facebook

    Recent posts on blogs I like:

    Randal O’Toole Gets High-Speed Rail Wrong

    Now that there’s decent chance of US investment in rail, Randal O’Toole is resurrecting his takes from the early Obama era, warning that high-speed rail is a multi-trillion dollar money sink. It’s not a good analysis, and in particular it gets the reality…

    via Pedestrian Observations May 12, 2021

    Collections: Teaching Paradox, Europa Universalis IV, Part II: Red Queens

    This is the second part in a series (I) that examines the historical assumptions behind Paradox Interactive’s grand strategy computer game set in the early modern period, Europa Universalis IV (EU4). Last time, we took a look at how EU4 was a game fundame…

    via A Collection of Unmitigated Pedantry May 7, 2021

    Books and websites on babies

    Several people I know are expecting a first baby soon, and I wrote up notes for one of them. Might as well share here too: Medical:Scott Alexander’s Biodeterminist’s Guide to Parenting is an interesting read, and some parts are actionable.  If you live in…

    via The whole sky April 14, 2021

    more     (via openring)


  • Posts
  • RSS
  • ◂◂RSS
  • Contact