Resource Documents by Hemphill, R.R.
Kelley, N.D.; Hemphill, R.R.; and McKenna, H.E.
Methodology for Assessment of Wind Turbine Noise Generation
[Abstract] The detailed analysis of a series of acoustic measurements taken near several large wind turbines (100 kW and above) has identified the maximum acoustic energy as being concentrated in the low-frequency audible and subaudible ranges, usually less than 100 Hz. These measurements have also shown any reported community annoyance associated with turbine operations has often been related to the degree of coherent impulsiveness present and the subsequent harmonic coupling of acoustic energy to residential structures. Thus, one technique to . . . Complete article »
Kelley, N.D.; McKenna, H.E.; Hemphill, R.R.; Etter, C.L.; Garrelts, R.L.; and Linn, N.C.
Acoustic Noise Associated with the MOD-1 Wind Turbine: Its Source, Impact, and Control
This report summarizes extensive research by staff of the Solar Energy Research Institute and its subcontractors conducted to establish the origin and possible amelioration of acoustic disturbances associated with the operation of the DOE/NASA MOD-1 wind turbine installed near Boone, North Carolina. Results have shown that the most probable source of this acoustic annoyance was the transient, unsteady aerodynamic lift imparted to the turbine blades as they passed through the lee wakes of the large cylindrical tower supports. Nearby residents . . . Complete article »
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