Performance and Loads Investigation of Optimum Speed Rotors

Abstract:

Performance of helicopters can be significantly influenced by rotor speed variation. A comprehensive model is built to exam the influences of rotating speed on performance and blade loads of a variable speed rotor. The results indicate that for a 2,200kg gross weight helicopter, power reduction is up to 30% at 100km/h by slowing the rotor properly. For lower gross weights, the reductions in rotor rotating speed and power savings are more apparent. The optimum rotating speed may cause a 20.5% increase in endurance and 8.5% in range by thoroughly consuming 400kg of fuel. Rotor RPM variation has an important effect on blade loads. For 100km/h and 2,200kg gross weight, amplitudes for most of the harmonic loads decrease with reduced rotor RPM.

• Periodical: Applied Mechanics and Materials (Volume 607)
• Pages: 500-506
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.607.500
• Online since: July 2014
• Authors: Shi Ming Liu*, Wei Dong Yang, Ling Hua Dong, Jie Wu
• Keywords: Helicopter, Load, Performance, Power, Rotor, Variable Speed

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