Concept explainers
Cooling method for gas turbines. Refer to the Journal of Engineering for Gas Turbines and Power (January 2005) study of gas turbines augmented with high-pressure inlet fogging, Exercise 7.94 (p. 407). The researchers classified gas turbines into three categories: traditional, advanced, and aeroderivative. Summary statistics on heat rate (kilojoules per kilowatt per hour) for each of the three types of gas turbines are shown in the Minitab printout (at the top of the next page).
- a. Is there sufficient evidence of a difference between the
mean heat rates of traditional augmented gas turbines and aeroderivative augmented gas turbines? Test using α = .05. - b. Is there sufficient evidence of a difference between the mean heat rates of advanced augmented gas turbines and aeroderivative augmented gas turbines? Test using α = .05.
- c. Conduct a test (at α = .05 ) for equality of heat rate variances for traditional and aeroderivative augmented gas turbines. Use the result to make a statement about the validity of the inference derived in part a.
- d. Conduct a test (at α = .05 ) for equality of heat rate variances for advanced and aeroderivative augmented gas turbines. Use the result to make a statement about the validity of the inference derived in part b.
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