Cooling method for gas turbines. Refer to the Journal of Engineering for Gas Turbines and Power (January 2005) study of a high-pressure inlet fogging method for a gas turbine engine, Exercise 4.13 (p. 188). Recall that you fit a first- order model for heat rate (y) as a function of speed (x1 ), inlet temperature (x2 ), exhaust temperature (x3 ), cycle pressure ratio (x4 ), and air flow rate (x5 ) to data saved in the GASTURBINE file.

Researchers hypothesize that the linear relationship between heat rate (y) and temperature (both inlet and exhaust) depends on air flow rate. Write a model for heat rate that incorporates the researchers’ theories.