Consider a gas turbine that has a pressure ratio of 8 and operates on the Brayton cycle with regeneration between the temperature limits of 20 deg C and 900 deg C. If the specific heat ratio of the working fluid is 1.33, the highest thermal efficiency this gas turbine can have isQuestion 4Select one:a.42%b.49%c.58%d.63%e.69%
Question
Consider a gas turbine that has a pressure ratio of 8 and operates on the Brayton cycle with regeneration between the temperature limits of 20 deg C and 900 deg C. If the specific heat ratio of the working fluid is 1.33, the highest thermal efficiency this gas turbine can have isQuestion 4Select one:a.42%b.49%c.58%d.63%e.69%
Solution
The thermal efficiency of a Brayton cycle with regeneration can be calculated using the formula:
η = 1 - (1 / r^(γ - 1))
where: η is the thermal efficiency, r is the pressure ratio, and γ is the specific heat ratio.
Given in the problem, r = 8 and γ = 1.33. Substituting these values into the formula, we get:
η = 1 - (1 / 8^(1.33 - 1))
Solving this equation gives us the thermal efficiency of the gas turbine.
Please note that the temperature limits given in the problem are not needed to solve for the thermal efficiency in this case, as the efficiency of a Brayton cycle with regeneration is not dependent on the temperature limits.
After calculating the above expression, we get the thermal efficiency as 0.49 or 49%. So, the correct answer is (b) 49%.
Similar Questions
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