Open Systems

[MarkE]

Quote from: MarkE on Today at 01:09:25 PM

    MH Tinman has gotten himself really, really lost.  He'll find out sooner or later just how badly he has deceived himself when he tries to make something based on his misconceptions work.

Im lost? lol.

Yes, you are very badly lost on very fundamental issues.

Quote MarkE-When you let the piston move out unopposed to its original position, then to your great surprise you would find that the pressure is greater than the 5psi gage that you had at the start.

Wow Mark,you have just invented an OU device. We now have more stored force than we started with. How did you do that when it was clearly stated that it was a frictionless device.

No, this is again where you are just lost.  Please avail yourself to any of the many thousands of reputable online references because you stopped paying attention to any of the correct explanations offered by others and myself here a long time ago.

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    Tinman I really do not know what has gotten into you.  You have become obstinately ignorant and shrill.

Well if that isnt the pot calling the kettle black.
You shun my work simply because it dosnt comply with your 200 year old physics. If we dont all agree with you,then we become shrills--.now that is being ignorant. By the way,many of us are still waiting for your physics to tell us what the magnetic force is,as your physics knows all about magnetic fields!right?!

You have made a series of incorrect statements that are refuted left and right by that "200 year old" physics that you disdain.  Experiment after experiment refutes your assertions.

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If you choose to act like a jerk at the same time, then again so be it.

A jerk would be some one that just believes what they read,and that is the be all and end all-->not having done any experimental work at all on the system in question.

My definition is one who engages in personal attack rather than debate the merits of their arguments.  "Yes it is!" and "No it isn't!" are declarations, not arguments.

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    I've explained to you repeatedly what would occur in your set-up

im sorry,but !Elvis has left the building! is just not enough. Tell me exactly what energies you think have been depleted(or transfered outside the system) in my system when the piston is opperated.
I will then show you that Elvis is dead,and simply cannot leave the building.

For the umpteenth time, if the piston does work on the outside world, then it transfers energy to the outside world.  The gas exerts force on the piston.  It exerts that force in the direction of motion.  It performs work.  That work comes from the internal energy of the gas.  Going the opposite way:  External force must be applied to the piston in order to force the gas into a smaller volume.  That force is again applied in the direction of motion.  That is external work that is performed on the gas.  That work increases the internal energy of the gas.  It increases nRT and consequently the PV product just as surely as the piston pushing out against a load transfers internal energy from the gas to the external load.  In each case given enough time where the ambient temperature is constant, the environment being a giant heat sink/source, the temperatures will equilibriate, and the gas volume will have almost identically the same nRT and therefore PV product as before.  That is the static case.  The industrial world is based on these simple facts that you reject.

It is funny as an engineer watching you physics guys meassureing small parts of a system after an action within that system has taken place,while over looking everything that took place over the system as a whole after that action. You deal in ideals that dont exist,and messurements are made from these ideals. Then you have variables to make things work out when things dont quite add up. As an engineer,we deal in absolutes,and systems as a whole.

You suffer from a fundamental misconception and have defied all patient efforts to disabuse you of that false notion.

Just found this

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    A real process exchanges work with the outside world, specifically, the piston is supposed to do something useful when it moves, the energy to do that cools the gas, just like a can of dusting spray cools when gas is released, and the n*R*T has now gone down inside Tinman's system, meaning that it has given up the energy that performed the external work:

This is a clasic example of what i was saying in the above statement-failing to look at the complete process.-->The total heat energy is still in the system as a whole-->no heat energy has left the system-Elvis is dead,and cannot walk. This is where your 200 year old physics,and your own blindness Mark,MH and the new guru libre are going to come unstuck. This is the very same attitude that holds all man kind back from being free of fossil fuels. 365 days in a year-oh but every 4 years we have to throw another day in there to make things all work out--screwed up with out time definitions there some where-->but hey,what the hell,it's all good.

Now,which of you knows about/or the mathematics to equate total force within a sealed vessel?-->you know,force per unit area x area total. And which of you is able to calculate total heat energy within a given volume? Lets put engineering up against your physics,and we'll see where that lead's us.

What would you like to equate the force to?  Force is not energy.  The total force is the product of the surface area of the vessel and the pressure.  Since for a given internal energy and vessel volume we will have a corresponding pressure that is independent of the surface area of the vessel, for a given internal energy we can design vessels that minimize or maximize force on a given internal surface by our choice of the vessel shape. 

[LibreEnergia]

Well it's time you went back to engineering school,as things have changed. We now look at systems as a whole,and all events that will take place around that system in question. Foe example,when meassureing pressure in a sealed vessel,it is no longer acceptable to use psi. You now have to account for total force over a given(total) area.

I don't think I have ever used psi to measure pressure.

Back when I learned engineering the measurement of pressure was "force per unit area". The basic unit in the SI system is the 'Pascal' which is equal to a force of 1 newton per square metre. I realise America is somewhat late to the party but your comment shows extraordinary ignorance for someone who claims to be an engineer.

Now... back to the explanation of why heat and work are convertible and why heat increases when you compress gas, on which you still hold mistaken conclusions. 

Thermal energy is the sum of all the kinetic energies of all the particles in the system. When that energy flows between two bodies we call it heat transfer. It is distinct from temperature which is a measure of the potential for heat to flow from one body to another.

To understand why doing work increases the amount of thermal energy in a system and hence the ability to transfer heat, imagine what would happen if we compressed a gas in a cylinder at very high speed, close the actual velocity of the particles in it. In air that would be around 900 km/hr.  or approx. the speed of sound.

The piston would then be striking the particles much faster than they normally impact it. That collision imparts a force on the particles and causes their velocity to increase. How could it not..? unless you want to argue the toss on newton's laws of motion.

Since the particles have been accelerated the internal thermal energy increases as it is simply the sum of the kinetic energies of all the particles. Internal energy is increased. The ability is transfer heat is increased.

Of course, the same process occurs at any speed of compression, but it useful to imagine a piston advancing into a gas at high speed to get an intuitive feel for why the velocity and hence 'heat' of those particles increases.

[profitis]

Mark E says: ' just like a can of
dusting spray cools when gas is released, and the n*R*T has now
gone down inside Tinman's system, meaning that it has given up
the energy that performed the external work'


I say: correct.energy that was supplied by the environment.not by tinman.tinman is merely swtiching phases reversibly >liquid>gas>liquid>gas>liquid>gas.tinman is a traffic cop. Tinman is a transistor switch while the environment does the work

[LibreEnergia]

Mark E says: ' just like a can of
dusting spray cools when gas is released, and the n*R*T has now
gone down inside Tinman's system, meaning that it has given up
the energy that performed the external work'


I say: correct.energy that was supplied by the environment.not by tinman.tinman is merely swtiching phases reversibly >liquid>gas>liquid>gas>liquid>gas.tinman is a traffic cop. Tinman is a transistor switch while the environment does the work

I'm sure there are much better refrigerants than 'HH0', which doesn't actually exist in that form anyway. The gas is H2 and O2 and it combines back to H20.  Since that process is at most 70% efficient for a round trip then you'd be far better off using something else as the working fluid.

Like ammonia etc.

[profitis]

Libre says:  'I'm sure there are much better refrigerants than 'HH0', which
doesn't actually exist in that form anyway. The gas is H2 and O2
and it combines back to H20.  Since that process is at most 70%
efficient for a round trip then you'd be far better off using
something else as the working fluid.
Like ammonia etc'

I say: or a singular gas eg h2 alone.at low currents.then we can push it up to 95% reversability and fall within the window of gainland