## Analytic studies of sound pressures inside the duct of ducted propellersJoseph A. Drischler, United States. National Aeronautics and Space Administration, Langley Research Center Pressure distribution analysis of sound inside duct of ducted propellers. |

### What people are saying - Write a review

We haven't found any reviews in the usual places.

### Common terms and phrases

31 of reference acoustic pressure doublets angular velocity APPENDIX attenuate axial direction Bessel functions center of pressure coaxial circular cylinder concentrating the loading coordinates decibels defined by equation distribution of concentrating duct of variations duct radius duct wall ducted fans due to thrust effect of tip effective Mach numbers effective radius equation A29 equation A5 exponential figure 17 figures 21 Fourier free-stream Mach number ft-lbf Green's function harmonic content harmonic number hub-tip ratio inequality is satisfied infinite coaxial circular inside the duct Langley Research Center level with harmonic modes n'th harmonic nondimensional overall sound-pressure level present analysis pressure distribution inside pressure doublets acting pressure due propeller blade propeller disk propeller loading radial pressure distribution rotational tip Mach separation of variables sound-pressure field SPLov thrust and torque tip clearance tip Mach number U.S. Customary Units upper inequality Variation of sound-pressure variations in propeller velocity potential wave equation zero