Question on energy and exergy analysis.

In summary, a frictionless piston cylinder device contains a saturated liquid-vapor mixture at 100 °C and 600 kJ of heat is transferred to the surroundings at 25°C. This causes some of the water vapor in the cylinder to condense. The problem is unclear on what properties are being solved for and how to use the first law with unknown boundary work.
  • #1
nothingkwt
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Homework Statement



A frictionless piston cylinder device contains a saturated liquid-vapor mixture at 100 °C. During a constant pressure process 600 kJ of heat is transferred to the surroundings which is at 25°C. As a result, part of the water vapor contained in the cylinder condenses.



Homework Equations


Q-Wb = mΔu


The Attempt at a Solution




If I wanted to find out the properties of the water how can I do so if they only gave me 1 intensive property, and I don't know how to use the first law since there is boundary work (?) that I can't figure out how much since ΔV is unknown.
 
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  • #2
I am afraid it is unclear what is being solved for...
 

FAQ: Question on energy and exergy analysis.

1. What is the difference between energy and exergy analysis?

Energy analysis is a method used to analyze the energy flows in a system, while exergy analysis is a method used to analyze the efficiency of a system in converting energy into useful work.

2. Why is exergy analysis important in energy systems?

Exergy analysis allows for a more comprehensive understanding of the efficiency and potential for improvement in energy systems, as it takes into account the quality of energy and the irreversibilities in the system.

3. How is exergy calculated in a system?

Exergy is calculated by determining the maximum work that can be obtained from a system when it is brought into equilibrium with its surroundings, using the Second Law of Thermodynamics.

4. What are the limitations of exergy analysis?

Exergy analysis does not consider the costs associated with the production and transportation of energy, and it also does not take into account the environmental impacts of energy systems.

5. How can exergy analysis be used to improve energy efficiency?

Exergy analysis can be used to identify areas of inefficiency in a system, allowing for targeted improvements to be made. It can also be used to compare different energy systems and determine the most efficient option.

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