Re: Constant volume compression/expansion-displacer chamber analysis-heat powered mechanical amplifier
Posted: Mon Jun 05, 2023 4:45 pm
Home on a break from the shop, so thought I'd look in.VincentG wrote: ↑Mon Jun 05, 2023 1:50 pm Tom I do fundamentally disagree with that, but putting that aside...I think its strange to view dumping heat into the cold sink as a waste when the whole reason these engines run is through temperature differences.
The fact that we have unlimited ambient cooling should be taken advantage of to the fullest extent IMO. We are essentially given a free cold power stroke with no net work loss.
To me not taking advantage of this would be like not using hydro electric power from a dam. Or driving your car up a hill and then not coasting down.
The elusive "cold hole" is just an exaggerated version of what we already have with ground temperature or ambient cooling. Its far easier to make heat than cold, and as you have stated(correctly I believe) there is more power to be had from 300k to 600k than from 0k to 300k, for instance.
The problem with that ("I think its strange to view dumping heat into the cold sink as a waste when the whole reason these engines run is through temperature differences")
The "whole reason" as it turns out (IMO) these engines run is not a temperature difference. It's a pressure difference between the internal pressure and external pressure.
Adding heat increases the internal pressure to do work, the work output uses up the energy and the pressure drops back down. Your playing against atmospheric pressure.
To.my way of thinking a "cold sink" doesn't utilize or "use up" the input energy through work output, it just throws it away.
Cooling might be useful in moderation but I imagine it would be better to use a heat pump cooling the cold side if needed by transferring the heat over to the hot side, but you can't go below zero pressure, so even that has its limits. Too much cooling and you'll just be robbing heat from the hot side before it can do any work.
If the engine is utilizing all the heat input the pressure drop comes naturally.
On top of that, a Stirling engine is already it's own heat pump.
I just think that it may be possible to design a more powerful heat engine if the whole apparatus for transferring heat to the cold side were eliminated and instead, more attention was given to fully utilizing tbe heat, then the cooling would take care of itself.
I can't say at this point in time that this is a proven theory, I may be all wrong, but it's the direction all my experimenting has led me to and why I designed my "Ringbom" engine conversion without a cold sink or a displacer. Granted, it may not work but I feel I have to at least give it a try.