The ideal efficiency of a non-regenerative Brayton cycle with rising pressure ratio will_________________?
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Answer: A. increase
Explanation
Thermal efficiency of a non-regenerative Brayton cycle depends mathematically on the compressor pressure ratio. Increasing the pressure ratio expands the temperature limits within the cycle turbine expansion stage. Higher pressure ratios lead directly to greater thermal efficiency for ideal gas turbine engine operations. The Brayton cycle efficiency formula expresses performance as a function of specific heat ratio and pressure ratio. Non-regenerative cycles lack heat exchangers to recover exhaust gas thermal energy before combustion. Higher pressure ratios require robust compressor designs to handle elevated discharge temperatures safely.
Modern aerospace gas turbines operate at high pressure ratios to maximize fuel efficiency during flight. Industrial power generation gas turbines push pressure limits to extract maximum electrical output per fuel unit. Material science limitations often restrict how high pressure ratios can be raised in practical engines. Option B is incorrect because efficiency improves rather than drops with rising pressure ratios. Option C contradicts thermodynamic formulas that prove efficiency changes with pressure ratio variations. Option D is wrong because the efficiency trend with pressure ratio is mathematically predictable and clear.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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