Axial Spacing Effects on Rotor-Rotor Interaction Noise and Vibration in a Contra-Rotating Fan

Figure 11

The monitoring point diagram and directivity curve of CRF under different axial spacing. (a) Monitoring point diagram. (b) 310 Hz. (c) 620 Hz. (d) 930 Hz.

(a)

(b)

(c)

(d)