Curie Effect Magnetic Heat Engine

Curie Point Magnetic Heat Engine -- How it works

The heat engine uses a principle of magnetism discovered by Pierre Curie. He studied the effects of temperature on magnetism. Ferromagnetism covers the field of normal magnetism that people typically associate with magnets. All normal magnets and the materials that are attracted to magnets are ferromagnetic materials. Pierre Curie discovered that ferromagnetic materials have a critical temperature at which the material loses its ferromagnetic behavior. This is known as its Curie Point.

As an example, a piece of iron (Fe) at room temperature is strongly attracted to a magnet. Heat the iron to a temperature of 770 C, which is its Curie Point, it loses its ferromagnetism behavior and it is no longer attracted to a magnet. If we let the iron cool, it regains its ferromagnetic behavior and is attracted to the magnet again.

We can use this property to construct a small swinger type heat engine. The heat engine uses a nickel alloy wire that has a low Curie Point, see drawing to right. When the wire is at room temperature it is attracted to the magnet, and swings close to the magnet. In this position, labeled B in the drawing, it is heated by the flame of a small birthday cake candle. When the material temperature reaches its Curie Point, it loses it ferromagnetism and falls away from the magnet, to position A, and out of the candle flame. As the wire cools it regains its ferromagnetism and is attracted to the magnet again, where it swings back up toward the magnet to position B and back into the candle flame. This process repeats, swinging the nickel alloy wire back and forth.

Category:

Science & Technology

Tags:

• heat
• engine
• curie
• effect
• magnetic

[johni1084]

I tried this using ferrite beads. It worked sort of. You need two candles (or flames) to heat the ferrite bead right in front of the magnet and the ferrite bead just past the magnet. This forces magnet attraction to the to rotate the wheel. With only one flame or candle, only the ferrite bead in front on the magnet loses attraction. The beads one either side, are mutually attracted to the magnet and locks the wheel in position preventing and resisting any wheel rotation. Hope that helps you.

[johni1084]

I plan to make it solar powered.

[aguuled]

The silhouette of this video would have looked like something else.

[mangyscavenger]

In theory, tab would be attracted to magnet, turning wheel as magnet pulls it, then heated at the sticking point, which would allow it to move away from magnet. Magnet would attract next tab, again turning the wheel. And so on, and so on.

LOL, who knows, maybe it would work.

[mangyscavenger]

Extremely interesting. YouTube is an awesome learning tool. How could this be used for real work? Not sure, but I'll take a stab at it.

You could make a wheel with metal on the outer rim spaced properly. Put a powerful magnet close to the rim. Put a candle at the point where metal "sticks" to the magnet. (The metal Monel might work best, needing low heat for this)

[egn83b]

Nice