Questions tagged [heat-engine]
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Contradiction in the Carnot Cycle?
The carnot cycle is reversible, because the temperature difference between heat reservoir and fluid is extremely low, so that heat can flow in both directions.
Also, the carnot cycle is described as ...
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Will a Modified Maxwellian Demon Experiment Using Charged Particles Be Able to Recycle Heat?
(If necessary this experiment can be conducted in an environment where gravity is negligible to avoid gravitational effects.)
Two adjacent containers are filled with a homogenous gas composed of ...
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Do thermodynamic cycles occur only in human-made machines?
Intuitively, it seems like heat engines and refrigerators require a good bit of technology to make a working substance pass through different thermodynamic states and then finally return to the ...
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Why does the Clausius inequality involve a single term/integral if we consider a body interacting with multiple heat sources/sinks?
I see that the Clausius inequality was derived for a system interacting with multiple bodies at temperatures $T_{1}, T_{2}, \ldots, T_{n}$ and heat exchanges $\delta Q_{1}, \delta Q_{2}, \ldots, \...
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In a fast moving space ship, can you harvest energy from the radiation background?
In a fast moving space ship (let's say a meaningful portion of c), radiation coming from the front is blue-shifted, while the one coming from behind is red-shifted. Meaning the part of the universe ...
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Effect of adiabatic compression of air with cooling water
In the context of a hypothetical method for CAES, I was comparing the following two scenarios:
Assume that in the first case air is compressed in an adiabatic process from ambient pressure to ...
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Does temperature difference alone equate to stored energy?
A heat engine uses a temperature difference in a hot side and a cold side to produce work. But when you run a heat engine, with a fixed amount of heat in the hot and cold sides until equilibrium is ...
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Validity of second law of thermodynamics?
Is second law of thermodynamics only valid for isolated systems?
What about closed systems and open systems? Since there is exchange of both mass and energy in open systems, wouldn't that violate 2nd ...
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Heat gun element to heat a glass furnace?
The general function of a heat gun is to increase the temperature of ambient air to a set temperature. My broken heat gun is rated at 1100 F.
I have successfully melted a soda bottle in a campfire and ...
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Confusion about finding enthalpy change
I have a confusion about something in the following question.
An ideal diesel engine has a compression ratio of
20 and uses air as the working fluid. The state of air at the beginning of the ...
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What makes a perpetual motion machine of the second kind actually “perpetual”?
As I understand it, a perpetual motion machine does continuous work without additional energy input. If a perpetual motion machine of the second kind exists, it violates the second law of ...
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Shape of chamber in thermodynamic machine
Why doesn't the shape of the chamber in a thermodynamic machine/heat engine influence the efficency?
Wouldn't a bell / parabola / cone shaped chamber help turn brownian motion into mechanical work of ...
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Is there a specific commercial or experimental implementation of the Carnot cycle? [closed]
I have been unable to find an example of a Carnot engine implemented practically, beyond the drinking bird (which has not revolutionized technology as far as I know). I understand the Stirling and ...
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How does Heat flows in Carnot engine? [duplicate]
According to fundamental concept of thermal conduction, heat flows from higher temperature to lower temperature. As in Carnot cycle, there is isothermal expansion and compression as a process i.e. ...
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Analyzing $T$-$S$ diagrams
This is the motivation behind my question; what would the longest line therein translate into on a $p$-$V$ curve? It is evident that the horizontal line is an isothermal process and the vertical line ...
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