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ACTA AERONAUTICAET ASTRONAUTICA SINICA ›› 2017, Vol. 38 ›› Issue (6): 120746-120746.doi: 10.7527/S1000-6893.2016.120746

• Fluid Mechanics and Flight Mechanics • Previous Articles     Next Articles

Test on effects of porous permeable section on trailing edge noise

LIU Hanru, CHEN Nanshu   

  1. School of Power and Energy, Northwestern Polytechnical University, Xi'an 710072, China
  • Received:2016-09-05 Revised:2016-12-02 Online:2017-06-15 Published:2016-12-21
  • Supported by:

    National Natural Science Foundation of China (51506179);the Fundamental Research Funds for the Central Universities (3102016ZY018)

Abstract:

A novel porous permeable section of the trailing edge (TE) is designed and tested in acoustics wind tunnel using far-field microphone to investigate the effects of various flow conditions and material properties on the TE noise. The results show that the current porous permeable section causes extra cavity noise component. The 4.7% relative density of metal foam causes the minimum extra noise, and the granular porous materials produces less extra noise than that of metal foam. Under the symmetrical flow condition, the TE noise of porous flat plate contains the cavity tonal component which disappears under the artificial nonsymmetrical flow condition. It indicates that the pressure difference pushing the airflow pass through the porous surface is crucial for the design of the porous section. It is found that reducing the discrepancy of pressure distribution between artificial nonsymmetrical flow and practical nonsymmetrical airfoil, as well as reducing the excessive porous area, should be focused on during the design of porous section for TE noise reduction.

Key words: airfoil noise, porous materials, aeroacoustics, artificial pressure difference, acoustics wind tunnel

CLC Number: