magneto-hydrodynamic concepts

Got another vote for using electrostatics to reduce the overall power required to generate the ions for the MHD to act upon ... I was feeling like the lone ranger there for a while, glad that's over with ... 8- )

It's starting to look like I can use really fine wires bonded in parallel strands in a single layer the desired width to do the job ... so, the structure just got thinner and lighter than previous models.

The signal used to do this will be a slow rising sawtooth with a fast fall, sustaining the magnetic field longer in one direction before collapsing it quickly to start over. The sawtooth can be timed to the flow velocity but I'm not so sure you even need to do that because the field will mainly be used to repel the ions so they slip over the coils without creating a shear zone in the flow column. Having the fields go the wrong way for a small amount of time may not hurt overall performance enough to make the complexity of timing the acceleration and keeping the fields going in one direction worth the trouble.

This is a lot easier problem than accelerating the ion stream at the flow rate or faster, something you'd have to do with a MHD propulsion system. All that needs to happen is a patch of reduced shear to allow laminar flow to last significantly longer.

You can get hold of self adhesive copper or aluminium tape of varying widths that is thin enough to cut with scissors from companies who sell rf suppression aids. This might be easier/quicker to use than lots of wires.

In the UK someone like Chomerics or Rayproof are suppliers, dont know who you would use in the US.

Thanks Andy, will look into it, I've seen some things in catalogs that may work for this so will search around and check those suppliers to see what kind of things I might find here.

The prototype will use the OTS stuff, but I keep thinking about how to manufacture the concept and what would work for that as well ...

Check out Parlex especially the Flat Flexible Cable product line. This is laminated flat copper strips in customizable widths and spacings.

Why reinvent the wheel, Parlex looks like it can make anything I've been thinking of lately. Will have to get some spec's together and see what their opinions are, obviously they have a lot of experience with thin film wires and flexible PC boards, I like the additive products for concept a lot ...

Since the macro flow is going to move these ions downstream, all that's necessary is to break the bond between the air molecules and the surface to reduce drag, implying that the electrostatic source could be modified to receive a charge to repel the last batch of ions.

I like it ... no separate acceleration coils and circuitry, the ion generation hardware will contain additional circuitry to create a charge to repel the newly created batch of ions. So, there still will be a banded set of electrostatic conductors, these would switch between ion generation and repulsion harmonically to the macro flow similar in concept to a propulsion system but much simpler by virtue of only needing one type of conductor and far less power.

The latest architecture is getting back to thin conductors that essentially perform both functions, fairly high frequency and voltage to create ions and also creating a magnetic field force that attracts and repels them depending on the cycle. The trick with these is to ramp current for a longer real time in one direction of the cycle so overall efficiency is higher than a sine wave. Have also thought about sprayed-on ferrite dust and charging that. I like that approach a lot but it seems it won't have enough field strength to separate the ions from the surface, but, it may in fact create a cushion of ions that repel each other with enough strength to be effective at decreasing the molecular density in a way that reduces drag. Can't find much research for the ferrite idea.

dude man i love how you give such nice progress reports! i can't understand more than a tiny bit of it, but it's awesome. really gives a sense of progress.

EDIT: email me some pictures and stuff and i'll put up a website for you (with sigurd's help) on here/the new SRN website after ISDC. doesn't have to be a primary website, just something that'll get more exposure if it's hosted here and linked on the main page... (pending approval from sigurd).

Thanks dude, you made my day, definitely feel like the Lone Ranger at times with this stuff ...

EDIT: will try to get some diagrams and paragraphs for a website, even though I have my own I think this work is better on SRN

Even if you are the Lone Ranger, you've got at least one fan. I'm hoping you'll come up with something I can then use in vehicle design. I'm still fuzzy on how it's supposed to work, but as long as it does, I'm happy.

I'm gettin' there ... and from what I can tell so far this'll work once I figure out one of several ways that seem possible that I can afford to set up.

It's a pretty simple idea, the boundary layer is a really thin area right next to the skin of any vehicle in a fluid or gas. The molecules at the surface don't move while 6mm away they are almost up to the speed the vehicle is going so this area is in shear. The shear produces drag. All I'm trying to do is knock molecules away from the skin so they are free to move with the airstream for small sections of the wing to reduce the area in turbulent flow. This will reduce the drag and increase the lift a lot for very little "effort".

Since much of the final R&D will be pretty costly, all I'm doing now is exploring practical ways to do this and will pick the best one to create a proof-of-concept experiment that doesn't cost too much. Hopefully this will generate enough interest to go from there with a team ... :- )

Would it be possible to use this method to reduce airframe heating at very high speed? In particular, could an air breathing vehicle get up to orbital speed without melting?

I hesitate to speculate on too much yet, but from what I've been working on I believe that the friction can be reduced significantly and thus allow much higher speeds for the same applied propulsion. AFAIK heat will still be produced, but not as much per unit of power. Whether that's enough to get to orbital is hard to say, it's certainly moving in that direction. If the total surface of the vehicle is considered, including interior flow surfaces within the engines ... it'd be a lot closer than anything else I've studied to get to orbital velocity without rockets, but, I don't want to sound too positive about it because MHD hasn't been applied this way much, I've yet to find any research on the exact method I'm designing..

Right now I'm wrapped up in sprayed on designs and using distributed current fields across them to current sinks. I think using wires is too costly, will be too heavy and cumbersome to apply to vehicle surfaces so set that idea aside for a while (previous patents used the wire idea). Kinda' excited about the sprayed on idea (or gas diffusion if necessary), seems it'll work and it's way more practical as a manufacturing method.

Probably should mention that I'm using a computer generated bias signal for this, allows me to engineer the signal shape precisely, change frequency and voltage easier for testing. Once a preferred shape is discovered I can convert to solid state parts if that makes sense. It may be that as speed changes a computer generated bias is more practical to keep the signal optimized.