Is an Ideal Cycle Possible? Examining Enthalpy Values in a Lab Experiment

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An ideal cycle is theoretically unattainable due to inherent irreversibilities in real systems, but experimental results can approach ideal conditions. In a lab setup involving refrigeration, varying evaporator voltage while maintaining constant condenser pressure yielded enthalpy values that were nearly identical for both the actual cycle and the isentropic compression assumption. This unexpected similarity raises questions about the accuracy of the assumptions made in the experiment. The discussion highlights the complexities of thermodynamic cycles and the potential for experimental results to challenge theoretical expectations. Ultimately, while ideal cycles remain a theoretical construct, practical experiments can yield surprising results that merit further investigation.
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Is an ideal cycle possible? In a lab experiment that I have carried out, my enthalpy values for the cycle and the cycle assuming isentropic compression look like they are the same. I thought this was impossible but I am doubting myself now?

Thanks

Will
 
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skaboy607 said:
Is an ideal cycle possible? In a lab experiment that I have carried out, my enthalpy values for the cycle and the cycle assuming isentropic compression look like they are the same. I thought this was impossible but I am doubting myself now?

Thanks

Will

An ideal cycle is not achievable in reality due to irreversibilities. However, you may get arbitrarily close. What does your lab consist of exactly?

CS
 
We had a refrigeration setup and we varied the evaporator volts which varied the pressure whilst keeping the condensor pressure constant. At one particular pressure, the specific enthalpy and specific enthalpy (based on isentropic compression) are very close if not the same.

Will
 
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