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creating entorphy 2

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oscar

Mechanical
May 30, 2000
4
I was wondering if there is a process or system which can be set up which only gives off entorphy.  I know that entorphy is a by product of an irreversable process and that heat and work are the outputs that make the process irreversable, yet I would like to be able to just generate entrophy.
 
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Dear Oscar,<br><br>One thing for sure, we all have more entropy today then we had yesterday. Entropy is always increasing in a system if left to itself. One thermodynamic definition of entropy is: Function of the state of a system whose change in any differential reversible process is equal to the heat absorbed by the system from its surroundings divided by the absolute temperature of the system. I am not sure this helps you but maybe you could check a thermo textbook for more..........Bill B. <p>William H. Bernhart, P.E.<br><a href=mailto:bill.bernhart@tycoelectronics.com>bill.bernhart@tycoelectronics.com</a><br><a href= > </a><br>I work as a senior development engineer for AMP - Tyco Electronics located near Harrisburg, PA. I help design interconnections for areospace applications.
 
Entropy is astatiscal thermodynamics property comes out from various thermodynamics processes in the world, it is generated due to heat(work) exchange between systems and surroundings, refering to 2nd low of thermodynamics we found that the nett entropy between system and surroundings is always increased which have a philosophical implication,so we found that entropy is a result which we could not get it without&nbsp;&nbsp;a thermo dynamics process.<br><br>BYYY
 
Dear Oscar,<br><br>If we look at the very definitions of work and heat, it is the &quot;pulley work&quot; which defines thermodynamic work. So, as an example, if we take an empty box, fill it with gas at a pressure greater than surrounding's and isolate it (which means no heat or work should escape from or into the box), box becomes an isolated system. Now, puncture the box (or make a small hole/outlet which has smooth curvature so that heat does not generate when the gas escapes from the box), and allow the gas to escape until steady state is reached. Obviously, final pressure between the box(system) and the surroundings(atmosphere) will be the same. But the escaped gas cannot enter the box and bring the pressure to its initial value &quot;automatically&quot; without external work. As entropy can be defined as unavilability of work that has been done, &quot;free expansion&quot; discussed above may be considered as a process where no heat or work is done but entropy is still generated. <br><br>I hope I answered your question and I welcome any comments or flaws in my reasoning or understanding of this&nbsp;&nbsp;tricky concept of entropy from anyone!<br><br>BYE
 
if a system were to undergo a cyclic process in which it came back to its earlier state after the process was completed, ie, same state condttions viz temperatur , pressure etc ,and does zero work and releases zero heat in the meanwhile then it would satisfy the &quot;pure entropy producer&quot; (Entropy would be produced for sure.. we cant help it)but ofcourse .. the question now is .. would such a proces be feasible ?
 
Entropy is the falling of energy from one order to a lower order and is a chaotic condition - It is quite a philisophical and maybe intangible in the order of life..We as humans are only energy after all and from the second law of thermodynamics - energy cannot be created or destroyed... so a non religious based evaluation of death might be that our energy dissipates by virtue of entropy to a lower order...How low??

essentially we are not jumping around like children with boundless energy at the age of 37 (at least i am not) so it is a parameter that becomes greater as time goes on....WHY ??

maybe tooooo deeep

Kieran
 
Dear Oscar,
What exactly do you mean when you say that you want to generate Entropy only ?? Is it that no other change should take place in the system ?? That, I don't think is possible in a sense because after all entropy is something which is generated as a result of a spontaneous change in the state of a system.
However a different approach is possible ... as you might know ... the state of a system made up of a pure substance can be defined by two independent properties. Now what could be done is that you take a sealed container of gas at a certain temp greater than the ambient ... let it cool down in some open space ... then, when the temp reached ambient ... just heat it up to the orginal temp ...as far as the container is concerned, some heat is added to it and some lost ... so there is no entropy change and the container is back to its original state ... but the overall entropy of the universe would have increased because of two irreversible processes ...

There is some level of ambiguity in this explaination and if anyone wants a discussion, please feel free to mail at vipul203@bigfoot.com


 
Oscar:

Heat transfer is another good example ...

Gordan
 
ALL, all diffusion processes are inherently irreversible. Thus, conduction heat transfer and eddy current generation are examples of pure entropy generators.
 
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