Reduction of Hypervelocity Heating with Elliptical Leading Edges.
Abstract
Elliptical shapes are considered for use on wing and fin leading edges and fuselage chines in hypervelocity flight. Calculated distirbutions of heating rates and radiation equilibrium temperatures are presented for a family of ellipses at 0 and 60-degree angles of attack. Heating rates were obtained with a finite difference solution to the laminar compressible boundary layer equations combined with an empirically derived inviscid pressure law for two dimensional flow around elliptical cylinders. Reduction of peak heating rates from circular values is shown up to 17 percent with a blunt ellipse of axis ratio 0.6 at zero angle of attack, and 14 percent with a sharp ellipse of axis ratio 1.6 at 60-degree angle of attack for the re-entry condition studied. This represents a 140 degrees R drop in the radiation equilibrium wall temperature (with 0.8 emissivity) for zero attack angle, and 100 degrees R drop for 60-degree angle. The calculated temperature distributions are also used to find shapes having minimum surface area requiring protection above certain temperatures. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1972
- Accession Number
- AD0739869
Entities
People
- Daniel Weiss
Organizations
- Grumman