Diesel vs. Otto cycle efficiency: limiting behavior with cut-off ratio State when the Diesel cycle efficiency approaches the Otto cycle efficiency. Choose the correct condition.
Mechanical Engineering
Thermodynamics
Difficulty: Medium
Choose an option
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ACut-off is increased
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BCut-off is decreased
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CCut-off is zero
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DCut-off is constant
Answer
Correct Answer: Cut-off is zero
Explanation
ConceptDiesel cycle has heat addition at constant pressure with a finite cut-off ratio rc. As rc → 1 (i.e., cut-off → 0), the Diesel cycle heat addition tends to constant volume, and the cycle approaches the Otto cycle.
Final AnswerCut-off is zero