Engineering Board Exam Reviewer · Thermodynamics · hard
An ideal Diesel cycle has a compression ratio of 18 and a cutoff ratio of 2. What is its thermal efficiency? (k = 1.4)
- 68.53%
- 58.48%
- 63.16%
- 55.16%
Answer
C. 63.16%
Solution
= 1 - (1/rk-1) · [(rck - 1)/(k(rc - 1))] = 1 - (1/180.4)(1.6390/1.4) = 63.16%.
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