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Hi Thomas,

I haven't done it, but could certainly be an interesting topic to combine magnetic and thermal physics.

The tricky part in magnetics would probably be accurate material data regarding the Curie transition and in the thermal part a realistic approach to heating and cooling mechanisms.

Some of these concepts are actually not too complex and prototypes could easily be built. Modeling and prototyping together can be fun.

Look there (if you haven't already): www.aqpl43.dsl.pipex.com/MUSEUM/POWER/thermomagnetic/thermag.htm

Cheers
Edgar

Thanks Edgar

I saw that also while back on internet this information

Actually in 1969-1970 that was the subject of my freshmen year invention or innovation idea for our engineering introductory course

I have seen some people discuss the workings of such a design concept on the internet but haven't really looked into what research available on this subject over the years , ie if a practical device was ever made or brought to fruition

Having gone to Comsol class a few years ago and also to Ansys seminars I have been amazed with the integration of these modeling programs and level of analysis to bring to our desktops , and probably now the cloud and the tablets

It would be interesting to work backwards from known outputs also desired and see what materials can or are need to bring a actual practical useful device to work

I did look into ,material;s a few years ago that were available ,but not extensively

I also have some other methods that also may work using Mu metal shielding and applying heat to its Currie temperature.

I am not a thermodynamic engineer but the modeling capabilities with these programs could certianly help in determining if any new methods can be advantageous to explore

My intent was to use this as a heat loss converter from waste heat to electrical energy

But I have noticed that other more efficient processes with nano technology ;ie think Univ of Ariz , a a recent paper which shows an easier method to do this type of conversion

Anyways always thought it interesting idea to explore since not much info on Internet is available on this subject

Hi

What annoys me is the lack of decent dynamic analysis seen so far.
The thermal heat exchange dynamics is not really in favour of this kind of motors, in my understanding.
But nevertheless, COMSOL is a great tool to study and better assess such issues, and to view it globally

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Good luck
Ivar

That may be true about the thermal heat dynamics may not be in favor of this type of motor,

I guess you are also stating that Comsol doesn't support a decent dynamic analysis on this subject

i do understand that thermal analysis is quite a complicated field especially with transient analysis being proposed

My later idea instead of rotary motion was to take in waste heat as a source and forming a controlled multiple line of heat flow into a magnetic shield materials, to turn on and off the ability of a Mu metal from shielding and then not shielding a magnetic field.Since a collapsing magnetic field will be generated in this manner a coil of some sort will receive the collapsing field generating a EMF

That is with a constant magnetic field, generated at all times by some magnetic system or a high strength magnet, then shielded by the magnetic material with a coil surrounding such, the intervention of the turn on and off of the shield will cause the collapsing field.

The idea is that instead of allowing the magnet to loose and get back its magnetic as indicated in the Tesla and Edison pyromagnetic generator,idea of using its field field on cool down, which would probably be very slow to change , the shield if segmented into many pieces can be heated by waste heat sources and cooled much faster ,through heat exchangers,heat pipes and the magnetic field generated by such may be fast enough to obtain a generation of an electrical ac current.

It probably also would be to slow but the dynamics of the thermal process and the magnetic synchronized may get a power output in the coil,although maybe not very efficient.

But if with waste heat its lost anyways

Another thought was to actually use electrical current to heat shield and cool it.

Thus instead of waste heat a form of dc to ac transformation, or actually an ac input to the shield with an output in coil an ac will be generated.All dependent on the heat change ability of the shield.

An unusual type of transformer

The question then asks whether materials are available to do this

Hi

No in contrary: I believe COMSOL is absolutely the best tool to do a dynamic and static analysis of such systems !

It's "just" that my "guts feeling" is saying me this is not the most efficient system (but I might be wrong ;), on the other side, there is a lot of wasted heat around and such a system could take a place in a specific niche application.
But first it should be optimised from the schemas seen so far, and that is typically the type of things an engineer with some time could do with a tool like COMSOL, unfortunately I do not see any opening for "free time" before my retirement, still in some years ;)

On the other side, there are thermo-electric material generators too, they also need thermal gradients. But today one can do many things not possible a century ago.

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Good luck
Ivar