How does the presence of non-condensable gases affect the actual condensing pressure relative to the required pressure without them ____________________ ?
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Answer: A. will be higher
Explanation
The presence of non-condensable gases increases the total condensing pressure in a system. Dalton Law of partial pressures states that total pressure equals the sum of individual gas pressures. Trapped air adds its own partial pressure to the saturation pressure of the refrigerant vapor. Non-condensable gases such as air often leak into refrigeration systems operating below atmospheric pressure. Higher condensing pressure forces the compressor to work harder to reject heat to the environment. Purging systems are used to remove accumulated air and restore normal operating condensing pressures.
Elevated condensing pressures reduce refrigeration system coefficient of performance and increase power bills. Industrial plant operators regularly check for non-condensable gases to maintain optimal energy efficiency. High head pressure can trip safety cutouts, causing unexpected shutdowns of refrigeration machinery. Will be lower contradicts Dalton law because adding any gas component increases total system pressure. Will remain unaffected ignores the physical contribution of partial pressures from trapped gases. Unpredictable is incorrect because gas pressure behavior follows well established thermodynamic laws.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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