Propane driven Generator system

[russ_watters]

Off-topic posts split to a new thread: https://www.physicsforums.com/showthread.php?t=276588

 

[RonL]

After recent events I was surprised at how many views this thread has generated. Another thing that stood out to me is how little information is disclosed about overall design.

The recent comments about flywheels and their efficiency, produced a thought in my mind, and I would like see what others might think.

First let me repeat why propane is the liquid of choice.
1. Availability
2. Can be combusted as an additional heat source.
3. It's ability to absorb heat from the atmosphere (even through the night) if system conditions are correct.
4. Non-conductive, non-combustionable, in a closed system.
5. Liquid form can serve as both coolant, and lubericant for electrical and moving parts.
6. Elimination of internal ice buildup using certain phase change devices (as opposed to water steam).

Now for the question in mind, considering that the objective is to heat the liquid propane and produce pressure in the system.

Would a flywheel completely submerged in liquid propane serve it's full purpose and at the same time all resistance to the liquid friction, and bearing drag, even motor losses are absorbed by the liquid, thus producing a 100% use of energy at that point?

Ron

 

[Mech_Engineer]

First let me repeat why propane is the liquid of choice.
4. Non-conductive, non-combustionable, in a closed system.

Gasoline is also non-flammable in a "closed system." That doesn't detract from the fact that it is very hazardous, especially if a small leak occurs. Propane is even more dangerous if a small leak occurs because it is gaseous at STP.

5. Liquid form can serve as [a] lubericant for electrical and moving parts.

I don't think this is necessarily true, unless you have some data on lubricating moving parts using liquid propane. just because its a liquid doesn't mean its a good lubricant.

Would a flywheel completely submerged in liquid propane serve it's full purpose and at the same time all resistance to the liquid friction, and bearing drag, even motor losses are absorbed by the liquid, thus producing a 100% use of energy at that point?

What exactly are you asking here? Are you trying to heat the propane with a submerged flywheel now? What's wrong with just heating it with the sun?

 

[FredGarvin]

I would never think of lubricating something with liquid propane. The system would have to be at high pressure and the small amount of heat you would pull out would undoubtedly vaporize it. It's vapor pressure at 100°F is 172 psig. It's boiling point at atmospheric pressure is -44°F. You would seriously be looking at a cooling system comperable to what is used with liquid hydrogen in rocket motors. Not to mention what Mech already pointed out that its lubricity is probably non existent. You would never get a lubrication system like that to work. What you would end up with is a system that is ripe for a fire.

 

[RonL]

This might be one supporting link, and although it talks of refining contaminated oil that is normally considered waste, I think it supports the idea of propane liquid being a carrier of a certain amount of pure base oil that will serve as a lubricant to any moving parts such as bearings, and air motor vanes. Filters would remove any contaminates produced from wear in the moving parts.

http://www.interlineresources.com/Used%20Oil%20Re-Refining?showall=1

Having exposure to high pressure hydraulic systems that turn and slide, I understand the concerne for leaks, but all moving parts can be contained within the pressure tank, and any thermal transfer parts (that might need to be outside the tank) will be no different than a typical AC system.

The point of the flywheel question, was all energy normally considered waste is in fact used in the very act of contributing heat to the system.
Not sure a flywheel is needed, it was just a thought about efficiency.

Ron