Reconsider Prob. 15–22E. Using an appropriate software, investigate the effect of frontal area on the annual fuel consumption of the car. Let the frontal area vary from 10 to 30 ft² in increments of 2 ft². Tabulate and plot the results.

In Prob.

To reduce the drag coefficient and thus to improve the fuel efficiency, the frontal area of a car is to be reduced. Determine the amount of fuel and money saved per year as a result of reducing the frontal area from 18 to 15 ft². Assume the car is driven 12,000 mi a year at an average speed of 55 mi/h. Take the density and price of gasoline to be 50 lbm/ft³ and $3.10/gal, respectively; the density of air to be 0.075 lbm/ft³; the heating value of gasoline to be 20,000 Btu/lbm; and the overall efficiency of the engine to be 30 percent.