Given identical compression ratios and equal heat addition_________________?
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Answer: A. Otto cycle is more efficient than Diesel cycle
Explanation
For the same compression ratio and heat input, the Otto cycle is more efficient than the Diesel cycle. Heat addition in the Otto cycle occurs at constant volume rather than constant pressure. This thermodynamic difference results in higher peak temperatures and greater cycle efficiency. The Otto cycle models spark-ignition internal combustion engines fueled by gasoline. Compression ratio is the ratio of maximum to minimum cylinder volumes in the cycle. Comparing air-standard cycles provides insight into optimal engine design configurations.
Automotive engineering balances compression ratios and fuel characteristics to maximize efficiency. Engine designers choose cycle types based on required power output and fuel constraints. Understanding cycle efficiency helps improve fuel economy in modern passenger vehicles. Option B incorrectly reverses the thermodynamic efficiency relationship of the cycles. Option C is false because identical compression ratios and heat inputs yield distinct efficiencies. Option D ignores thermodynamic analysis proving Otto cycle superiority under these conditions.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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