Table 1 Determined spoiler angles for the audi A5 at two design points along with their aerodynamic characteristics at different Reynolds numbers.

From: Improving the aerodynamics of a fastback car body using a spoiler

Design points

Road conditions (relatively high speed)

Rapid deceleration conditions (aerodynamic braking)

Design parameters

\({C}_{d}\)

\({C}_{l}\)

Angle of spoiler (°)

\({C}_{d}\)

\({C}_{l}\)

Angle of spoiler (°)

Re = 4.87 × 106

0.310

− 0.0122

0

0.552

− 0.127

45

Re = 9.75 × 106

0.314

− 0.0208

0

0.610

− 0.1283

60

Re = 14.61 × 106

0.317

− 0.005

0

0.588

− 0.132

55