MHD Generator Head for an Oscillating Fluid Flow

This sounds like an interesting spin-off of sugarandfat's thread, and with luck may lead to some cross-talk between the two.

Right now, the only thing I know about MHD is what the letters stand for. Nonetheless, here may be a stab-in-the-dark conjecture: The flow rate of ions should correspond to current output, and the velocity may correspond to voltage output (big ?? especially on the latter).

On that very tentative basis, I did not see an advantage to diverging/converging nozzles or piping sections. For the moment, I'm just along for the ride, but I anticipate enjoying and learning from the threads and sites. Best of luck to both on your respective projects.

He and I have been corresponding/collaborating for some time on seperate but related projects.

I think you're close, but the magnetic field is what "drives" the ions to the electrodes - so field strength is also an important part of the picture.

This project really needs involvement of ME, EE, and physics types, and I'm wishing that discussions could be linked (joined) across CR4 sections for better collaboration.

I recall from a good generation ago, that MHD generators were a good idea for very high power. Erosion and cooling were the problem. Modern materials, maybe.

Go for it! Even, if you do not succeed completely, you have more than fair chance to advance the state of the art.

I recall from a good generation ago, that MHD generators were a good idea for very high power. Erosion and cooling were the problem. Modern materials, maybe.

AFAICT, much of the effort put into MHD was intended to improve efficiency of existing generator stations by adding a secondary energy extraction process to recover as much as possible from an (otherwise wasted) plasma stream.

One of the unavoidable drawbacks was that the hot gasses exiting the MHD head still carried away a significant amount of the original plasma stream's energy. My expectation is that by installing MHD heads in a closed system with an oscillating flow, the generation process overall efficiency will benefit from repeated passes of the ion-carrying media through the heads.

The approach I'm taking only requires 374-400°C operation, and media velocity will be considerably less than I would expect in a plasma-based system, so erosion is likely to be less of a problem. If electromagnets are used, cooling may become completely unnecessary, which (all by itself) might constitute a significant efficiency improvement.

Go for it! Even, if you do not succeed completely, you have more than fair chance to advance the state of the art.

I'm proceeding at full speed with a two-pronged approach: one will use a trough-type parabolic solar concentrator to power the reciprocating flow, and another will use an embedded Ni/H fusion reactor in a similarly-configured engine to power the flow. The fusion reactor is unproven, and will probably absorb most of my attention through the coming winter. If I have to master MHD alone from scratch, developments will proceed much more slowly, but I'm fairly certain that at least one of the two approaches will be successful.

I doubt that I'm doing much to advance the state of the art, since almost everything I'm doing involves fairly well-established/known principles. All I'm doing is attempting to connect old dots in a new way.