Thermo-magnetic motor

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Thermomagnetic motors (also known as Curie wheels, [1] Curie-motors [2] [3] and pyromagnetic motors [4] ) convert heat into kinetic energy using the thermomagnetic effect, [5] i.e., the influence of temperature on the magnetic material magnetization. [6]

Contents

Historical background

This technology dates back to 19th century, when a number of scientists submitted patents on the so-called "pyro-magnetic generators". [7] These systems operate in a magnetic Brayton cycle, in a reverse way of the magnetocaloric refrigerators. [8] Experiments have produced only extremely inefficient working prototypes, [9] [10] [11] however, thermodynamic analysis indicate that thermomagnetic motors present high efficiency related to Carnot efficiency for small temperature differences around the magnetic material Curie temperature. [8] [5] [12] The thermomagnetic motor principle has been studied as a possible actuator in smart materials, [13] being successful in the generation of electric energy from ultra-low temperature gradients. [14]

See also

Related Research Articles

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References

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