DESIGN AND TEST OF THE HIGH AERODYNAMIC PERFORMANCE LOW-NOISE FAN FOR 5.5- BY 4-M ACOUSTIC WIND TUNNEL

摘要

The arbitrary vortex method and some noise control methods are employed to design a high aerodynamic performance low noise axial fan in a 5.5- by 4-m acoustic wind tunnel. In the design process, better distribution of the axial velocity at the outlet of the fan stator is obtained by regulating the distribution of swirl velocity, and the noise generated by the fan is reduced by more reasonably matched rotor-stator blade number, stator backward-swept angle and rotor-stator spacing. The aerodynamic test results show that the wind speed required in the solid wall test section is satisfied, and when the fan rotational speed is 330rpm, the fan reaches the highest aerodynamic efficiency (95.7%) and the fan section also has the highest aerodynamic efficiency (90%). Moreover, the acoustic test results show that the Overall Sound Pressure Level (OASPL) at the fan inlet is 101 dB(A), and the OASPL at the fan outlet is 105 dB(A) when the wind speed in the open jet test section reaches 80m/s. The combination of the arbitrary vortex method with noise control methods is proved to be a good design approach for the axial fan of large acoustic wind tunnel.