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Scanning Magnetron Microwave

More complete solution for the heterogeneous heating habits of traditional microwaves.
  [vote for,

Microwave ovens heat unevenly. Many solutions have been proposed <link><link>. These solutions continue the ineffective and wasteful solution of moving the food about a bit. These solutions require an oven interior significantly larger than the object placed within, this is because ancient wisdom precludes the movement of large objects withing small spaces without damage.

So, Move the microwaves, they're lightweight and probably won't mind. You can do this in two ways: either mount the magnetron in a fixed position and have a wave-guide with a raster-scanning mirror. OR, simply tilt the magnetron around a bit so it sweeps round the interior.

This will mean the end of the turntable, but the writing's been on the wall for some time. Record and CD players have lost their once lofty position, even the mighty spinning-platter hard drive is on the way out.

On the plus side, we'll all be able to put big square plastic food containers in the microwave without it knocking on the door like a mournful chimp.

*I'd like to register my disgust at Google Chrome. It's spell check doesn't recognize "Magnetron".

bs0u0155, Sep 26 2013

Waltzing Turntable Waltzing_20MaGrillDa
[bs0u0155, Sep 26 2013]

Wankel Turntable Wankel_20Microwave_20Carousel
[bs0u0155, Sep 26 2013]

Microwave oven physics http://hyperphysics...e/waves/mwoven.html
Wavelength is included in the descriptions. [Vernon, Sep 26 2013]

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       "Stirrer" technology has been around for decades.   

       Moving the magnetron is problematic.   

       How do you maintain the coupling between the magnetron, the waveguide and the oven chamber ? Waveguides rely on specific resonant lengths. Change the length of a waveguide and the VSWR will go all to hell (a technical engineering term).   

       Moving the magnetron requires a flexible high-power coupling between the power supply and the magnetron, a high current low voltage link. But moving the magnetron and its power supply is a lot of mass and bulk so you end up with a big cabinet.   

       Magnetrons are thermionic devices. They don't like being bumped while they're running. In aircraft, there are elaborate shock-mounts and vibration isolation structures to protect them. Bulky, costs money.
8th of 7, Sep 26 2013

       In one sense the fundamental problem, behind the stuff that [8th of 7] mentioned, is the physical size of the microwaves. Their wavelength is about 12 centimeters, and the amplitude of a single photonic wavicle is also that size.   

       Note, normally "amplitude" refers to things like "total power level", but that's not what I'm talking about here. If you want to describe any single photon as a sine wave, then the difference between trough and crest, of that sine wave, always equals the wavelength. (And so microwaves are simply too "fat" to escape through the holes in the metal mesh that covers the glass door of the average microwave oven.)   

       If microwaves were smaller they would be easier to manipulate with small parts, as this Idea describes. But they are what they are, the "right" size associated with a high absorption rate by water molecules (and so those molecules acquire energy and get hotter).
Vernon, Sep 26 2013

       // If you want to describe any single photon as a sine wave, //   

       We don't. We want to describe it as a particle.   

       // microwaves are simply too "fat" //   

       That's totally sizeist, and an appalling thing to say. You should be ashamed of yourself.   

       // molecules acquire energy and get hotter //   

       Tautology. Same thing.
8th of 7, Sep 26 2013

       There's a glaring error at the beginning of your link, [Vernon]:   

       "By federal regulation, microwave ovens are limited to 5 milliwatts (mW) of microwave radiation per square centimeter at approximately 2 inches from the oven surface. This limit is far below the level known to harm people. The microwave radiation would be expected to drop off according to the inverse square law, so at 20 inches it would be down by about a factor of 100."   

       The inverse square law applies only to point sources. A microwave oven is itself more than 20 inches long.
spidermother, Sep 26 2013


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