Engineering topics

Pittman, James L.

Publications and source records attributed to Pittman, James L..

21 records · Page 2

NASA NTRS1987

Experimental flowfield visualization of a high alpha wing at Mach 1.62

Experimental oil-flow and tuft patterns and vapor-screen flow-visualization data were obtained on a cambered wing model at Mach 1.62 for an angle-of-attack range of 0 to 14 deg. These data were used as flow diagnostic tools along with surface-pressure and force data and full-potential theory calculations. A large separation bubble was found on the lower wing surface at low angle of attack. The high-angle-of-attack flowfield was characterized by a large attached-flow leading-edge expansion followed by a cross-flow shock. At 14 deg, the cross-flow shock apparently induced discrete regions of streamwise separated flow which were clearly indicated in the vapor-screen and oil-flow photographs.

Pittman, James L.↗

NASA NTRS1987

A strake design method for supersonic speeds and low lift

A method is presented for the design of a strake for a forebody typical of supersonic aircraft at typical cruise (low lift) conditions, in order to ensure attached flow on the strake upper surface. The method systematically varies strake camber and thickness until an attached flow surface pressure distribution is achieved. Surface pressures are computed by the full potential flow solver, NCOREL. The high-alpha flowfield of the strake is also investigated experimentally and computationally; a large vortex is noted on the strake leeside, together with a pair of vortices on the forebody upper centerline. The effect of sideslip on the high-alpha flowfield is also discussed.

Pittman, James L.↗

NASA NTRS1987

High-speed code validation

The topics are presented in viewgraph form and include the following: NFL body experiment; high-speed validation problems; 3-D Euler/Navier-Stokes inlet code; two-strut inlet configuration; pressure contours in two longitudinal planes; sidewall pressure distribution; pressure distribution on strut inner surface; inlet/forebody tests in 60 inch helium tunnel; pressure distributions on elliptical missile; code validations; small scale test apparatus; CARS nonintrusive measurements; optimized cone-derived waverider study; etc.

Barnwell, Richard W.↗