As shown in Fig. P9.74, the aerodynamic drag on a truck can be reduced by the use of appropriate air deflectors. A reduction in drag coefficient from \(C_{D}=0.96\) to \(C_{D}=0.70\) corresponds to a reduction of how many horsepower needed at a highway speed of \(65 \mathrm{mph}\)?

Fig. P9.74

Transcribed Image Text:

b=width = 10 ft Isabelle 2001 12 ft (a) C = 0.70 Isabelle 2001 (b) CD = 0.96