dedeleco wrote:If easy flow, the pressure is uniform and the gas on one side will never be compressed relative to the other making the monotherm impossible
This statement shows to those who follow that you did not take the trouble to correctly identify what we are talking about.
How could the answer to a question that has not been understood make sense?
For my part I think I understood the proposed device. I am even sure after taking the time to fully understand.
It was about understanding this:
when the piston moves slowly then we have "an easy flow" ... and in such a case, in fact, there is no pressure difference between the two compartments ... but this is precisely how their machine works !!! ...
Their machine works very well WITHOUT pressure difference between the two compartments.
You have not yet understood the principle of operation of their machine.
When the gaseous fluid is heated through the regenerator, there is a reversible adiabatic compression of ALL the molecules (those of BOTH compartments) which is induced, at constant total volume, by successive and local reversible isobaric transformations (in the regenerator, groups of molecules follow one another). A temperature higher than that of the hot spring is then reached on the hot side of the machine. The pressure is assumed to be the same for all molecules and wherever they are (whether in one compartment or the other or in the regenerator).
When the gaseous fluid is cooled by passing through the regenerator, there is a reversible adiabatic expansion of ALL the molecules (those of BOTH compartments) which is induced, at constant total volume, by successive and local reversible isobaric transformations (in the regenerator, molecules come and go). A temperature lower than that of the cold source is reached on the cold side of the machine. The pressure is assumed to be the same for all molecules and wherever they are (whether in one compartment or the other or in the regenerator).
Before making a heat balance, we will start by trying to make sure that we have understood what is at stake.
Then, we agree that this is a process that has never been used (to our knowledge) as a heat pump. This novelty will attract our attention since we do not know, at this stage of our discovery, what could be its interest and its possible field of application ...
On the basis of this interest which cannot fail to exist for scientific minds, curious, lovers of reflection, of culture, a more in-depth study will be well motivated.
And it is ONLY then that things get really interesting.
We then understand that there is no expenditure of mechanical energy in the sense that said expenditure is very small AND that it is not dependent on the exploitation OR NOT of the potential thermal energy appearing under the form of a temperature higher than that of the hot source or lower than that of the cold source ...
Then we understand that if the molecules do not mix when entering a compartment then they come out exactly at the temperature at which they entered it ...
When a compartment is full then all groups of molecules are at different temperatures (but, of course, at the same pressure).
If we then allow the groups of molecules to mix, we obtain an average temperature and we have an increase in entropy.
And that's when something amazing happens:
while the compartment is emptying (and it is on the hot OR cold side),
there is a variation of the pressure in all the system (for all the molecules) so that the molecules will leave at a variable temperature (increasing for the cold side and decreasing for the hot side). A secondary deltaT has appeared.
What about entropy during THIS phase?
Entropy decreased during this phase.
This assertion does not suffer any possible dispute.
But the gas then enters the regenerator and the secondary deltaT is destroyed by the thermal inertia of the regenerator.
But the secondary Delta can be exploited just before its inevitable disappearance.
Without spending mechanical energy ... the thermal energy spent seems to be the same as in the case where the groups of molecules do not mix when entering AND when leaving the compartments, in comparison with the case where they mix and where a secondary deltaT appears on the hot side AND the cold side.
The device is incredibly simple and surprising.
In the absence of a rigorous and in-depth study, we cannot rule out the possibility that this invention is a threat (or an opportunity) for the refrigeration industry (among others).
It is only on the basis of a good understanding of the above process that we will rethink (from a new angle) the Stirling engine.
Indeed, by adding a driving piston approximately 90 ° from the displacing piston, we have a Stirling engine. But it would then be a question of dimensioning it so as not to destroy the effect of the heat pump (the appearance of a temperature higher than that of the hot source and lower than that of the cold source). This seems important since it is these two maximum and minimum temperatures which give the maximum pressure variation. However, the greater this variation in pressure, the more power the engine has ... to compensate for the loss of power that would be obtained at a lower speed. This is what we learn on their website.
teatime