544
P. Liu
Fig. 7.138 Main components of aircraft aerodynamic noise sources
Fig. 7.139 Proportion of aerodynamic noise of the airframe and engine components
during the approach phase of the aircraft
scale vortices form the main source of noise (as shown in Fig. 7.143). For
the landing gear, the landing gear bay is a typical cavity structure. The cavity
flow-induced oscillation not only generates additional aerodynamic noise but
also causes unsteady load, so bluff body separation is the main reason for its
aerodynamic noise (as shown in Fig. 7.144).
The relative noise magnitude of these noise sources depends on the specific
configuration. Wind tunnel experiments (as shown in Fig. 7.145 and 7.146)
and flight tests consistently show that the noise of the lifting device accounts
for a large proportion of the airframe noise and cannot be ignored. Specific
P. Liu
Fig. 7.138 Main components of aircraft aerodynamic noise sources
Fig. 7.139 Proportion of aerodynamic noise of the airframe and engine components
during the approach phase of the aircraft
scale vortices form the main source of noise (as shown in Fig. 7.143). For
the landing gear, the landing gear bay is a typical cavity structure. The cavity
flow-induced oscillation not only generates additional aerodynamic noise but
also causes unsteady load, so bluff body separation is the main reason for its
aerodynamic noise (as shown in Fig. 7.144).
The relative noise magnitude of these noise sources depends on the specific
configuration. Wind tunnel experiments (as shown in Fig. 7.145 and 7.146)
and flight tests consistently show that the noise of the lifting device accounts
for a large proportion of the airframe noise and cannot be ignored. Specific