This link describes some of the development details of the Marquand engine. Good information for development of other air car applications.
In the beginning, this Englishman does some snippy bashing on Terry Miller which is typical of the academia crowd. No doubt he gained his info for this reference from The Unc, but of course does not give credit. Once you get past that section, and get over the feeling to travel all the way to England just to kick his butt, then the rest is worth keeping a copy for future reference, this is hands-on application material. Size is 17 Meg.
Post by Uncle Buddy on Feb 21, 2014 15:39:08 GMT -8
Is that the one with heat pipes? I have had a diagram of a Marquand air engine on my site forever but didn't know more info was available. I will be reading that. I wrote to him once, but there was no response.
The link has to be copied and pasted since proboards' software doesn't always do links right.
Of course Terry Miller opens himself to academic bashing by building a car with off-the-shelf parts...you should hear what he had to say about academia! Inventors don't specialize in tactfulness.
Post by Uncle Buddy on Feb 22, 2014 7:49:38 GMT -8
I'll be looking at that as I get the time. I looked at what he said about Terry and I think "snippy" was a good choice of wording. He probably got his info from me but his perusal of it was superficial. A good example, he kept doubting that Terry could really fuel up his car in four minutes, even called Terry a liar really. This fast refueling (from tank to tank, not waiting for a compressor to do its work) is one of the conventional air car's great advantages, including the Marquand air car or any conventional air car, so "snippy" was a nice way to put it. Terry explained exactly how the tank filling is done, some way as it's done in a fire house or a dive shop, by pressure equalization.
That said, no doubt the rest of the document is worth taking a look at. Heat pipes are especially a good idea because of no working parts, although the drawback of heat pipes is that every drop of refrigerant ever produced will eventually find its way into our atmosphere. But maybe if the right material were used for the heat pipe body, pure water could be used as a refrigerant. I don't know much about heat pipes.
The body does have good reference material. Air motor types and comparisons. Regenerative braking heat capture methods. Comparisons with electric cars. Some of his reasoning can be used for our project and we could use his thought structure as well. There are good photos and diagrams. This is a good paper for reference. Nothing on acoustics or waves. But a working air car will definitely need to use regenerative braking and heat controls, so this is all good and applicable information. I would encourage the readers and lurkers out there to keep this one.
Thank you for finding this Tommy, I'm half way through. It is good. Very careful experiments and thoughtful analysis. I'm amazed at the heat pipe performance. He says improved heat transfer at higher flow rates is "not surprising" because of the increased temp differential but it is surprising in that without all the fins he carefully attached to the pipes, higher flow rates might not get enough heat transfer.
For the Unc - heat pipes are using ethanol - is that an OK refrigerant? (and water) but point taken about other problematic fluids.
Re his Terry Miller bashing, it was rather unkind and unsympathetic but it probably comes from a place of disbelief, Unc has written about how standard engineering teaching is very negative towards compressed air. In a way it is extraordinary that in his academic world he has pursued this at all. I had other criticisms too but have not made notes and can't remember them - sorry.
This heat pump tech with Neal acoustic magic would be great. Neal does use some heat exchange already.
Heat pipes are an awesome idea. I think I stopped talking about them so long ago because the implications of being able to move so much heat so fast without big bulky heat exchangers and without moving parts, opens up a new field even harder to believe than the "ordinary" free range air car that uses only the energy of the air injected into the tank. The injection concept as per Neal and Heaton puts the air into the tank whole hog, so all its heat is right where we want it. Add to that conserved compression heat. But add even more heat to that from the greater atmosphere, that not being put into the tank...why not!
If heat pipes use ethanol rather than ammonia or freon or something really nasty, so much the better. All fluids used for anything anywhere eventually will join the environment at large as leakage or spillage. I don't think the amount of ethanol used in heat pipes would be a problem. If your heat pipe sprung a leak, you could just top it off with vodka and plug the hole with one of those little umbrellas.