80
P. Liu
Fig. 2.1 Relative flight principle for aircraft
in the wind tunnel test than to make the model move in still air (as shown in
Figs. 2.2 and 2.3).
As early as the Italian Renaissance, the Italian scientist Leonardo da Vinci
(1452–1519, as shown in Fig. 1.3) studied the flight principle of birds and
Fig. 2.2 Wind tunnel test of scaled model of an aircraft
Fig. 2.3 Wind tunnel test with a prototype car