ACTA AERONAUTICAET ASTRONAUTICA SINICA >
Experimental investigation of flapwise and lagwise lower harmonic loads of a variable speed model rotor
Received date: 2015-03-30
Revised date: 2015-06-28
Online published: 2015-08-18
Supported by
National Natural Science Foundation of China(11472129);Aeronautical Science Foundation of China(2013ZA52014);Fundamental Research Funds for the Central Universities(NS2014007);A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
To investigate the characteristics of the flapwise and lagwise lower harmonic loads of variable speed rotors, a composite hingeless model rotor is tested in a wind tunnel. The zero and first three harmonic flapwise and lagwise root bending moments with the rotor speed, forward speed and rotor thrust are investigated. The test results indicate that reducing the speed of the model rotor can decrease the zero harmonic lagwise root bending moment, which means the reduction of the rotor power and the performance improvement of the rotor. At lower rotor speed, the first three flapwise harmonic loads increase with decreasing rotor speed. At lower rotor speeds, the first three lagwise loads are substantially large. When the rotor speed working near the first lagwise resonance rotor speed, the first two flapwise and lagwise loads are substantially large, and the variation of the third flapwise and lagwise loads are substantially small. Attention should be paid to the distinctly large first harmonic lagwise load, which can cause severe dynamic loads problems.
Key words： rotor; variable speed; loads; flapwise; lagwise; wind tunnel test
HUANG Dongsheng , WU Shijie , HAN Dong . Experimental investigation of flapwise and lagwise lower harmonic loads of a variable speed model rotor[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2016 , 37(3) : 873 -882 . DOI: 10.7527/S1000-6893.2015.0189
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