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Will graphene/diamond make the compressor isothermal?

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SImc1

Aerospace
Feb 25, 2010
4
Specifications.

Turbine inlet = 58 F
Turbine outlet = 37 F
Turbine outlet flow = 85 cfm
Turbine Q (heat extracted) -519 J

Compressor inlet = 70 F
Compressor outlet = 83 F
Compressor psig = 2.18
compressor outlet flow = 106 cfm
Compressor Q (heat added) 404 J

diamond thermal conductivity - 900 - 2320 w/mk
graphene -(4840±440) - (5300±480) w/mk


Assuming these parameters are true, we have followed the 2nd law of thermodynamics. We have a heat reservoir (compressor outlet at 83 F) and a cold sink (turbine outlet at 37 F).


Based off the 2nd law of thermo, if I embed a graphene/diamond heat exchanger system inside the compressor housing and it's connected to the cold sink turbine side, the 13 degree temperature rise from 70 F in the compressor housing should travel to the cold sink turbine.

Therefore, instead of the 13 degree temp rise causing resistance when compressing air, its being used to try to equalize the cold sink turbine.

Here is the question;

1. Will this cause the compressor to have an inlet temperature of 70 f and and outlet temperature of 70 f, making it an isothermal compressor?

 
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temperature doesn't travel.heat travels and temperature is a result of heat balance between added and removed heat.
temperature doesn't cause friction, friction causes temperature rise.
by removing heat, caused by friction (compressing), it doesn't nihilate the friction caused by compressing
 
temperature doesn't travel.heat travels and temperature is a result of heat balance between added and removed heat.
temperature doesn't cause friction, friction causes temperature rise.


13 F temp rise = 404 J. I assumed it was obvious, my fault.


by removing heat, caused by friction (compressing), it doesn't nihilate the friction caused by compressing


Heat of compression is internal energy and this internal energy opposes compression. This sounds like friction to me since friction is always opposing something.

With diamond/graphene in the way, this internal energy (404 J) has a new job. Its new job is to increase the internal energy of the turbine (cold sink) it has no choice. The next batch of air getting compressed wont have this internal energy in its way. Eventually the system will come to equilibrium.

With no diamond/graphene in it's (internal energy) way it will do what it's been doing for a long time and that is to oppose compression. Having internal energy just chill in the compressor housing is bad, its lazy, its a bum it needs a god damn job.

Lets just call this discussion creative thinking. So yea, the question remains.

1. Will this cause the compressor to have an inlet temperature of 70 f and and outlet temperature of 70 f, making it an isothermal compressor?
 
without wanting to spoil your creative thinking just a few thoughts:
heat sink:while nature tries to stay in equilibrum (which makes a gas move from high to low pressure or moves heat from high to low temperature), engineers need a place to dump all energy which can't be used for the purpose they design their machines.This unwanted energy needs to be dumped into nature, which puts properties to the heat sink:atmospheric pressure,air temperature, water temperature.For a turbine to produce more work,its inlet pressure/temperature needs to be increased, or its outlet pressure/temperature needs to be lowered (limited by the properties of the heat sink).
isothermal proces:a proces for which the temperature remains constant.by cooling the housing you get an adiabatic compression, followed by a isobaric cooling.
By using graphene,I wouldn't call it isothermal compression, but rather expensive compression.
 
Your usage of joules already indicates that you're in trouble. An engine as described is in thermal equilibrium, and the relevant unit is the watt, denoting heat FLOW.

As for your question, the answer is NO. Whatever heat is generated MUST flow out, therefore, there MUST be a temperature delta. You cannot make it arbitrarily small, as that requires a larger output area, and the heat incurs a temperature drop trying to get to edges of the larger area. Moreover, even if the exterior temperature is 70°F, that doesn't alleviate the internal temperature of the compressor.

TTFN

FAQ731-376
 
Ok, I'm satisfied. I got the answers and discussions I was looking for. Thanks everyone.
 
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