Charts for Estimating Downwash Behind Rectangular, Trapezoidal, and Triangular Wings at Supersonic Speeds
Abstract
Charts are presented for estimating the downwash behind wings in a supersonic stream. The wing plan forms for which computations are made include rectangular wings with reduced aspect ratios (cotangent of Mach angle times aspect ratio) of 2, 4, 8, and 12; trapezoidal wings with reduced aspect ratios ranging from 2 to 12.8 and taper ratios of 1/2 and 1/4; and triangular wings with reduced aspect ratios of B and 12. All the wings have supersonic leading and trailing edges. The charts are obtained on the basis of lifting-line theory. For each wing, charts of the downwash near the wing, the downwash in the Trefftz plane, and the spanwise distribution of loading are presented. The charts are applicable behind the wings in regions where the effect of the rolling up of the trailing vortex sheet is not excessive. The calculation of downwash farther downstream is briefly discussed. A procedure is indicated to correct for the displacement and the distortion of the trailing vortex sheet. The downwash behind wings with flaps is briefly considered.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1950
- Accession Number
- ADA380745
Entities
People
- Harold Mirels
- John L. Cummings
- Rudolph C. Haefeli
Organizations
- National Aeronautics and Space Administration