Otto and Brayton cycle efficiency calculator
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Result
Thermal efficiency58.48 %
Step-by-step solution
Air-standard Otto cycle
η = 1 − 1/rk−1 = 1 − 1/90.4 = 58.48%
Key formulas
- Isentropic, volume ratio
- T2/T1 = rk−1
- Isentropic, pressure ratio
- T2/T1 = rp(k−1)/k
- Otto efficiency
- η = 1 − 1/rk−1
- Diesel efficiency
- η = 1 − (1/rk−1)·(rck − 1)/(k(rc − 1))
- Brayton efficiency
- η = 1 − 1/rp(k−1)/k
- Heat added
- Otto: cv(T3 − T2) Diesel, Brayton: cp(T3 − T2)
- Brayton net work
- w = cp[(T3 − T4) − (T2 − T1)]
- Isentropic efficiencies
- wc = wc,s/ηc, wt = ηt·wt,s
- Cold air
- k = 1.4, cp = 1.005, cv = 0.718 kJ/(kg·K)
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