It depends on what kind of system you are looking at. For engines, water-steam cycle, there can be isothermal process. Try looking at Rankine, Brayton and Otto Cycles.

It depends on what kind of system you are looking at. For engines, water-steam cycle, there can be isothermal process. Try looking at Rankine, Brayton and Otto Cycles.

It depends on what kind of system you are looking at. For engines, water-steam cycle, there can be isothermal process. Try looking at Rankine, Brayton and Otto Cycles.

The question you ask is complex and ambiguous. A gas can absorb energy and increase its pressure rather than volume or a mix of both.

I think you really need to look at a thermodynamics textbook, starting with the ideal gas equation. I would recommend "Thermodynamics: An Engineering Approach", by Cengel and Boles, which is very readable.

Do not forget, beyond the ideal comes reality and no system is 100% efficient.

The question you ask is complex and ambiguous. A gas can absorb energy and increase its pressure rather than volume or a mix of both.

I think you really need to look at a thermodynamics textbook, starting with the ideal gas equation. I would recommend "Thermodynamics: An Engineering Approach", by Cengel and Boles, which is very readable.

Do not forget, beyond the ideal comes reality and no system is 100% efficient.

The question you ask is complex and ambiguous. A gas can absorb energy and increase its pressure rather than volume or a mix of both.

I think you really need to look at a thermodynamics textbook, starting with the ideal gas equation. I would recommend "Thermodynamics: An Engineering Approach", by Cengel and Boles, which is very readable.

Do not forget, beyond the ideal comes reality and no system is 100% efficient.

Thank you Lynton!


The real problem is using a cooling cycle to reduce the temperature of the power line.


If evaporation of one kind of coolant (density is ρ1) can absorb heat k1. And then the compressor compress the coolant to ρ2 for condensation, this procedure costs energy k2.

The temperature of conductor(e.g. copper line) decreases n centidegree (can be calculated by specific heat), so the Joule heat is reduced by k3(I^2*R, where R is reduced since temperature is low) correspondingly.


Assume that there is no out energy source. In above procedure, it seems energy required is k2(by compressor), and the energy saving is the k3(Joule heat).

Other parts in the procedure are pure heat exchange.


What's the relationship between k2 and k3? Is it possible to make k2 << k3(in case large current I)?

Thank you Lynton!


The real problem is using a cooling cycle to reduce the temperature of the power line.


If evaporation of one kind of coolant (density is ρ1) can absorb heat k1. And then the compressor compress the coolant to ρ2 for condensation, this procedure costs energy k2.

The temperature of conductor(e.g. copper line) decreases n centidegree (can be calculated by specific heat), so the Joule heat is reduced by k3(I^2*R, where R is reduced since temperature is low) correspondingly.


Assume that there is no out energy source. In above procedure, it seems energy required is k2(by compressor), and the energy saving is the k3(Joule heat).

Other parts in the procedure are pure heat exchange.


What's the relationship between k2 and k3? Is it possible to make k2 << k3(in case large current I)?

Thank you Lynton!


The real problem is using a cooling cycle to reduce the temperature of the power line.


If evaporation of one kind of coolant (density is ρ1) can absorb heat k1. And then the compressor compress the coolant to ρ2 for condensation, this procedure costs energy k2.

The temperature of conductor(e.g. copper line) decreases n centidegree (can be calculated by specific heat), so the Joule heat is reduced by k3(I^2*R, where R is reduced since temperature is low) correspondingly.


Assume that there is no out energy source. In above procedure, it seems energy required is k2(by compressor), and the energy saving is the k3(Joule heat).

Other parts in the procedure are pure heat exchange.


What's the relationship between k2 and k3? Is it possible to make k2 << k3(in case large current I)?