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Jack wrote: ↑Thu May 23, 2024 3:10 am In the past I didn't always get what you (Tom) were talking about. But I think I've come to a similar conclusion as you during my recent research.

I've been looking into Tesla turbines in great detail and have a configuration in mind that eventually might work as an ambient heat engine.
This is going away from Stirling engines, but fits this topic.

What if, for a "cold hole", we were to create a vacuum. But a continuous vacuum between a pump and a turbine.
The pump would draw in fluid through a nozzle onto a turbine. The turbine in turn powers the pump and hopefully has some leftover.
The nozzle, if sized correctly, will squeeze the fluid and turn all the stored kinetic energy in the same direction and give the fluid speed onto the turbine. Because the fluid is pulled through the nozzle into a vacuum it gets cold but fast. Then it does work on the turbine, which heats it up a little before being pumped out again.

As Tom mentioned somewhere earlier in this thread, this theoretically would also work better with a load.
And I didn't used to think this would work in ambient air, because the pump will have to pump it into ambient air pressure. But what this pump basically does is put back in the heat so the fluid goes back to ambient pressure. If the pump alone had to do this it wouldn't work, but this thread made me realize that the pump can take ambient heat to bring the fluid back up to pressure.

So basically cooling ambient air while having work output.

I've started ordering parts to do the first experiments on this contraption.
The first goal would be to make this work with a bigger temperature differential. But after that I'm going for the full Monty.

Does this make sense?

I've been waiting to see if you might post a diagram as MikeB requested before commenting.

Getting more out from a turbine/pump combination seems less than unlikely. IMO

I drew a diagram of a similar turbine/pump 'cold steam" setup I posted on another forum a few years ago:
A rather off the top of my head and sloppy drawing with a few changes/corrections.

A bit difficult to follow even for me, looking at it now a few years later.

I don't know if you've seen that other forum discussion:

http://www.energeticforum.com/forum/ene ... ect/page20

Unfortunately the OP seems to be MIA so the discussion/project status is unknown.

Yeah I've come across Paul in my research recently. I was a short time member of his Patreon.
I'll spend some time reading that thread though, as I haven't seen that before.

I'll also try to get something on paper, but the next few days will be quite busy for me, so it might take a bit.

I missed some posts I see.

With the vacuum cleaner analogy in mind. I'm not proposing to have the motor/pump pull so hard that it creates a cold vacuum because of decompression.
What would happen in you plugged the hose of the vacuum cleaner with your hand and leave a small gap. Air rushes in and your fingers get cold because the internal energy is turned into kinetic energy.

If I can get it just right it would be so cold the water vapor momentarily condenses as it hits the turbine. Greatly increasing viscosity of the working fluid, air.

The question is, can that kinetic energy be more than the pump needs to "pull it in"

Jack wrote: ↑Tue May 28, 2024 5:25 am I missed some posts I see.

With the vacuum cleaner analogy in mind. I'm not proposing to have the motor/pump pull so hard that it creates a cold vacuum because of decompression.
What would happen in you plugged the hose of the vacuum cleaner with your hand and leave a small gap. Air rushes in and your fingers get cold because the internal energy is turned into kinetic energy.

If I can get it just right it would be so cold the water vapor momentarily condenses as it hits the turbine. Greatly increasing viscosity of the working fluid, air.

The question is, can that kinetic energy be more than the pump needs to "pull it in"

The general idea those guys seem to be working on is along the same lines as Tesla's "cold hole" in that the "cold hole" theoretically, only needs to be created once to start the process.

The water in the boiler, then, is boiled in a vacuum (saturated vapor) using ambient heat.

This "cold steam" then, expands driving a turbine.

Exiting the turbine you have cold "steam" that has lost internal energy, gotten colder, and so will condense. As it condensed it leaves a vacuum which pulls in more "cold steam".

Using ice to help condense the vapor, I think they have proven that this process actually works, but so far, afaik, not well enough to keep the ice cold.

I think they've done it in winter with the condenser / ice chest outside in the winter air to keep it cool.

What they seem to have so far is a way to generate some power from rather low grade waste heat.

I'm somewhat doubtful it will turn out to be very practical because steam, cold or otherwise, and phase change processes in general, are an excellent way of moving heat. When the steam condenses it releases heat. Hard to keep the condenser cold because a lot of heat went into making the steam. Probably next to impossible to remove it all through the expansion turbine.

An air cycle refrigeration system on the other hand does not use phase change. Relatively speaking, I think that in an air cycle system the turbine does not have such a big job removing all that latent heat of vaporization being carried by the steam.

Also, not limited by the freezing point of water, so colder temperatures are possible.

Anyway, a refrigeration system to MOVE the heat is really only 1/2 the equation.

The other 1/2 is a heat engine to convert the heat.

At least that's how I look at it.

Yeah that's what they're working on. But it seems wasteful of heat. And so far it seems to be testing max power output. They have a few ideas that I don't fully agree with and would like to prove otherwise.

They seem to rely on hotter gasses increasing in viscosity. But that entails that you have to be pushing the heat onto the turbine. And this turbine can't get any energy from heat itself.

I have a different idea about that.
The turbine works on viscosity and kinetic energy. So the heat energy should be turned into kinetic energy before being sent to the turbine. With the right nozzle that's possible.
It just so happens that water vapor condenses when it's cooled. Increasing the viscosity greatly.
So now you have fast cold water through the turbine.

Missed one detail. Jeremiah is working with a heated vacuum tank on one side and an ambient condensor on the other.
He's producing quite a bit of power with that. But as I explained above, it seems wasteful and short lived.

Paul on the other hand. I'm not exactly sure what he's trying. Difficult to get information from or to make sense of his posts or videos.

Jack wrote: ↑Tue May 28, 2024 10:01 pm Missed one detail. Jeremiah is working with a heated vacuum tank on one side and an ambient condensor on the other.
...

That appears to be the case recently, His older videos from several years ago were much more targeted on utilizing ambient heat.

I think he's perhaps being taken down a different course by his handler.

Haha yeah Paul (the guy posting in that thread you linked, I'm reading it all) likes to make himself sound important.

The thread actually explains more about Paul's motivations and development direction than his Patreon. I'm understanding more about his supposed discoveries from the Tesla patents.
He very much fixates on that and sometimes attributes things that he doesn't show any proof for.

It turns out he's thinking in the same direction I am with the ambient air machine. With the main distinction that he seems to think the turbine will power the pump without a shaft connection, while I don't see that happening and hope to put them on one shaft.
For a targeted output the one shaft should work. Dual shafts would be more versatile, but in my mind would need some kind of gearing.

I also don't really understand where he gets the supersonic perifery speeds.
Supersonic fluid speed, ok. But Tesla himself wrote about these turbines that he found they made most power when the fluid is going twice the speed of the perifery. Which would put it at "half supersonic".

However, mine are just thought experiments so far. I'm hoping to test in a few months.

Jack wrote: ↑Wed May 29, 2024 4:58 pm Haha yeah Paul ....

I was actually referring to Aaron Murakami

https://youtu.be/04XYOs0mx9o

Jeremiah has been under his supervision for the past couple of years.

Ah yeah since his previous partner died. But Jeremiah was going in the heated fluid direction before already.

Aaron gives me the wrong "vibes" though. Just from what I gather from the internet though.

There's another guy, Charlie Solis, he's going down a similar road, but seems to be more profit motivated.

I'm a member of Jeremiah's Patreon. In his latest setup he has a big radiator with fans as a condensor. So still waisting a huge amount of heat. I feel that's in search of high output power and self regulation.
I my opinion, you can't claim high efficiency if you need to cool your condensor that much.

He's trying to find a self regulating situation that uses the centrifugal head pressure to regulate the incoming flow.

But in my view that's extremely inefficient. The turbine can't do anything with pressure or heat. And building that up at the place where you are going to make the most power, the perifery, is kind of strange.
He mentions many times, when talking about the two stage turbine, that Tesla talks about any engine being more efficient when reducing back pressure. But then immediately turns around and says he wants to create back pressure in the perifery of the turbine to regulate it. That might work, but is extremely limiting to the one thing that the turbine wants, kinetic energy.

https://www.dropbox.com/scl/fi/23vj8239 ... vdwmj&dl=0

This is the quick drawing of what I have in mind.
A pump creating a vacuum which pulls in fluid through a nozzle and a turbine.
I drew them separately, but I think they should be on the same shaft and the vacuum chamber in that case would just be the open spaces in the centres of the discs.

The perfect nozzle would turn the incoming fluid's internal energy into kinetic energy. Because it's being pulled through into a vacuum that fluid won't encounter much resistance except for the discs it'll have to do work on.

I'm guessing this setup would need very specific circumstances to work with ambient air, but should work better with a delta t, obviously.

I drew the fluid path on both the turbine and pump disc. It should spend as much time as necessary between the turbine discs to transfer the kinetic energy. And as little time as possible between the pump discs. So the pump doesn't need a housing in my view. Just discs flinging cold air into the atmosphere.

Jack wrote: ↑Wed May 29, 2024 8:30 pm Ah yeah since his previous partner died. But Jeremiah was going in the heated fluid direction before already.
...

Perhaps it was the departed partner who was into the ambient heat aspect. In that case I wouldn't expect anything more of interest to emerge from the new partnership.


I don't really see any chance.whatsoever of that working, to be honest.

Looks a bit like someone has seen a diagram of a "Steam injector" (as used to top up steam engine boilers) and failed to understand the magic involved.

Aaron apparently, in his own words in this podcast thinks suppression of technology, at least in some circumstances, is "just good business practice".

https://www.podchaser.com/podcasts/the- ... -150784081

Hard to determine who are the "good guys" and who are the "bad guys" sometimes.

https://douktris.wordpress.com/2015/03/ ... urakami-2/

I'm not suggesting there is necessarily any substance to the accusations aimed at Aaron, just something to be aware of. There are always two sides to every story.