removing the achilles heal of stirling motors

Discussion on Stirling or "hot air" engines (all types)
auret
Posts: 21
Joined: Mon Jan 04, 2016 6:19 am

removing the achilles heal of stirling motors

Post by auret »

Earlier today I lodged a provisional patent titled GATED HEAT MOTOR in Australia. Basically I have found a way, very simple way, to circumvent the issues associated with trying to get the heat and the cool energy through thick walls in high pressure devices. I have posted enough detail on the facebook group GATED HEAT MOTOR for you to know what I am all about.

This is it gentlemen. This is the time of the heat motor. I have done what I do best, and now it's your turn to show the world what you are made of. Respect my ownership of the methodology and I will work with you.

Kind regards,
Derek
auret
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Joined: Mon Jan 04, 2016 6:19 am

Re: removing the achilles heal of stirling motors

Post by auret »

Ian S C
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Location: New Zealand

Re: removing the achilles heal of stirling motors

Post by Ian S C »

Derek, have you built a proof of concept motor, to see if the theory and practice match up?
Ian S C
auret
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Re: removing the achilles heal of stirling motors

Post by auret »

The invention is about 4 days old Ian. I'm proposing to build the first one as an immediately useable water pump using 70 C and 35 C inputs. I believe that is best. I will be working from first principles so expect something out of the box, harping to the distant past.
Ian S C
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Joined: Thu Dec 02, 2010 5:15 am
Location: New Zealand

Re: removing the achilles heal of stirling motors

Post by Ian S C »

Derek, I know it's summer in Australia, but surely you can get cooler than 35*C for the cold end, perhaps with water cooling by using the water that is pumped by the motor to pass through a water jacket before passing on, this was the common method used by the old pumping engines.
Ian S C
auret
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Joined: Mon Jan 04, 2016 6:19 am

Re: removing the achilles heal of stirling motors

Post by auret »

Funny thing is Ian, I have been throwing designs around all night, and am trending towards existing designs, which seem very logical. Having said that, and knowing that I require a high pressure machine, a water jacket on the outside negates my tech, without which the 35 C differential will be eroded in the walls. As to pumping water then, if the machine trends towards existing designs, I may as well put an alternator on it and be done with it. That is my current thinking.
auret
Posts: 21
Joined: Mon Jan 04, 2016 6:19 am

Re: removing the achilles heal of stirling motors

Post by auret »

Now I can sleep, design complete. Am ready to build. 2.45 am here
auret
Posts: 21
Joined: Mon Jan 04, 2016 6:19 am

Re: removing the achilles heal of stirling motors

Post by auret »

Ok I haven't shown my
gated heat motor
gated heat motor
nugget.jpg (86.54 KiB) Viewed 10655 times
methodology on the cooling side only the heating side but this pic will show you my thinking
auret
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Joined: Mon Jan 04, 2016 6:19 am

Re: removing the achilles heal of stirling motors

Post by auret »

Although I have no repeated my methodology on the cooling side, nor shown insulation on the inside of the vessel the displacer runs in, not shown quite a few things, I believe running at 4rpm, the above engine will easily covert exhaust gases into useable energy. This device is a bit out there, so I will next show how my methodology would work in a STD Stirling motor, which obviously will be easier to digest.
auret
Posts: 21
Joined: Mon Jan 04, 2016 6:19 am

Re: removing the achilles heal of stirling motors

Post by auret »

I trust you can see the thin walls between the working fluid and the hot and cold sources, that you understand the pumping technique to achieve this. So to all the believers in Stirling technology, this is our time.
Attachments
matilda
matilda
matilda.jpg (102.74 KiB) Viewed 10654 times
Bumpkin
Posts: 280
Joined: Fri Mar 02, 2012 1:42 pm

Re: removing the achilles heal of stirling motors

Post by Bumpkin »

Hi auret. Welcome to the forum, I always welcome ideas that make me think.

"I trust you can see the thin walls between the working fluid and the hot and cold sources, that you understand the pumping technique to achieve this."

Actually no I can't see it, but I want to. Terminology like gate and impedance makes me wonder if you have a thermal version of an electronic solid state relay. If so, it could have great significance to certain heat engines, but I can't see how it applies to Stirlings, where the heat flow is always in one direction - in the hot end and out the cold end - and the only reciprocating heat exchange is at the regenerator. Your mention of a different pumping system puts me in mind of the Ericsson engine where (as I understand it,) a large heat exchange area can be employed without contributing to dead space. Otherwise it seems like separate pressurized heat exchangers would just move the issues of thermal transfer through high-pressure walls to another spot.

Respectfully hoping for further enlightenment,

Bumpkin
auret
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Joined: Mon Jan 04, 2016 6:19 am

Re: removing the achilles heal of stirling motors

Post by auret »

Bumpkin thank you for the response, I can help/explain.

First and foremost, the one way heat transfer of the Stirling is not altered in any way. the pumping actions are a separate methodology that does the following, and for this let us just consider the heat source quite rightly at one end and the device.

Heat needs to progress through a thickness of material to influence the working fluid. what we do here, is basically pump hot liquid to inside that thickness and expose the heat to the working fluid through, in the case of "Matilda", a lesser thickness of material.

The integrity of the device remains, as we still have the thick walls, but we have bypassed the need for thermal transference through them. To explain how we do that, consider an example that we pass the exhaust gasses of a vehicle into a vessel that is unable to withstand high pressure. The benefits are easy transference of heat through thin walls. next.....

Next we use a bilge pump and return, to cycle that hot liquid into a random insulated pressure vessel with thick walls. Then we use the same bilge pump method, with return, to cycle that heated liquid from that random vessel through the Stirling motor pressure walls (on the hot end), and "show" that heated liquid to the working fluid from behind a thin wall, as in my Matilda drawing.

The random vessel, with its thick walls and the nature of liquid incompressibility, makes this possible.

Alternatively, in the drawing of Nugget, and quite rightly as you put it going back to earlier heat engine designs, the hot liquid is exposed dierecly to the working fluid. Let me just have another go at explaining NUGGET.

Nugget has 2 cylinders filled with stainless steel scarf, or similar items of mass. When the liquid is in the left cylinder it cools the scarf therein, and that scarf cools the working fluid (white in the drawing) when the working fluid is drawn into that left cylinder, similarly, in the right chamber, when the hot liquid (red), fills the chamber it heats the scarf (Mass) therein, and when the liquid recedes, the working fluid (gas), is heated by that scarf. I apologise to readers who see this as obvious. My method (Australian Patent number assigned), as explained in "Matilda" above shows how to get for example the waste heat from a vehicles exhaust, into the inside of those pressure vessels with a bilge pump, rather than slowly through a thick wall.

At first glance one would naturally scoff at the 300bar annotation, but consider that each stroke of a device like this, and I envisage 4 rpm, each stroke would impart massive amounts of energy either to or from the working fluid, given a version of nugget might have say 40 litres of working fluid at 300 bar, and the mass of scarf to be perhaps 12kg in each cylinder..... what I haven't shown in Nugget is the back pressure vessel attached where I have annotated (work done), the hydraulic drive and alternator there, or the water pump. The surface area of 12 kg of scarf or similar, basically replicates a set of lungs, something we could not In some cases do previously with those thick wall design restrictions in these motors.

I'm sorry for the long explanation, am ready to answer all questions. Again, just respect my ownership of the methodology (patent) and then in return I can be forthcoming, and we can go solve some problems.
auret
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Joined: Mon Jan 04, 2016 6:19 am

Re: removing the achilles heal of stirling motors

Post by auret »

And by the way Bumpkin, I do know that you, Ian and 3/4 of the people on this site have greater heat motor experience than I, so kindly be patient with my explanations. In what you quoted above, I should have used the word respectively after the word sources, sorry for that.
Bumpkin
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Re: removing the achilles heal of stirling motors

Post by Bumpkin »

Auret, I like these forum exchanges for the thought-provoking aspects, whether of understanding or confusion. I reckon I see the gist of your idea now. For my own purposes I'm less concerned about getting heat through the walls than I am about the internal exchange between the walls and the air, but I'm a low-pressure guy. :big smile:

Bumpkin
auret
Posts: 21
Joined: Mon Jan 04, 2016 6:19 am

Re: removing the achilles heal of stirling motors

Post by auret »

LOL Bumpkin

Thank you.
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