Flight Investigation of the Surface Pressure Distribution and the Flow Field Around a Conical and Two Spherical Nonrotating Full Scale Propeller Spinners
Abstract
A flight investigation has been made on three nonrotating full-scale propeller spinners at free-stream Mach numbers of 0.70 to 0.96 to determine the surface-pressure distribution and the magnitude and radial extent of the influence of each spinner on the local flow field. One spinner was a conventional conical spinner. The other two spinners had conical forebodies and spherical midsections that provided a mechanically simple means of affording an aerodynamically clean blade seal. The departure from stream conditions in the propeller plane of the conical spinner and the 60 deg spherical spinner extended beyond the 1.3-spinner-radius station; whereas, with the 45 deg spherical spinner, stream conditions were reached at the 1.3-spinner-radius station. High peak negative pressure coefficients occurred over the spherical section of both spherical spinners between the cone-sphere juncture and the blade center line. The local surface Mach numbers in this region are approximately 0.4 higher than that at free-stream Mach number of 0.95. The effect of yaw on both the surface-pressure distribution and the local flow field was investigated over the top and bottom surfaces of the 45 deg spherical spinner and was found to be small for the test conditions. Unfavorable flow separation occurred over the rear portion of the spherical spinners. This flow separation caused mild buffeting of the airplane above a free-stream Mach number of 0.72 with the 60 deg spherical spinner and above 0.83 with the 45 deg spherical spinner.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1955
- Accession Number
- ADA377332
Entities
People
- Elwood F. Scheithauser
- Jerome B. Hammack
- Milton L. Windler
Organizations
- National Aeronautics and Space Administration