Thermodynamics Question. Determine Quality of Two Phase Ammonia.

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SUMMARY

The discussion focuses on determining the quality of two-phase ammonia, specifically addressing discrepancies in calculated values. The user asserts that the quality for both samples is 1.00, despite expectations that lower temperatures would result in decreased quality due to reduced vaporization. The specific volume values referenced are sourced from the textbook's appendices on Properties of Saturated Ammonia (Liquid Vapor). Additionally, the user highlights incorrect units and values in the ammonia property tables used for calculations.

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  • Understanding of thermodynamic properties, specifically for ammonia.
  • Familiarity with two-phase systems in thermodynamics.
  • Knowledge of specific volume calculations and units.
  • Access to ammonia property tables for accurate data reference.
NEXT STEPS
  • Review the Properties of Saturated Ammonia (Liquid Vapor) tables for accuracy.
  • Learn about the significance of quality in two-phase systems.
  • Investigate the relationship between temperature and vapor quality in refrigerants.
  • Explore the correct units for specific volume in thermodynamic calculations.
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Students studying thermodynamics, engineers working with refrigeration systems, and anyone involved in the analysis of phase changes in ammonia.

kdhutchi
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I have attached a copy of my homework paper to this post. I'm fairly certain the answers are not correct. The quality for both parts is 1.00. In addition, the quality increases (to the fourth decimal place) in the 0.0 degree Fahrenheit sample. I'd expect the quality to go down due to less heat energy leading to less vapor. The specific volume values were obtained from my textbook's appendices titled: Properties of Saturated Ammonia (Liquid Vapor).

Also, I tried attaching just the document, but received the "invalid File" remark. I was hoping to just attach the doc to ease replies. Editing the document would be easier than a full fledged post! I'm using 2010 if that helps.
 

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Your formula is correct but your ammonia properties and units are incorrect.

Units should be volume / mass, like the total specific volume they provided.

Also, as a check: vg / vf is about equal to 50 for ammonia in this range. Your values are much higher.

Check again your ammonia property tables.
 

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