Accession Number : ADA319701

Title :   Development and Testing of a New Optimum Design Code for Hypersonic Wind Tunnel Nozzles, Including Boundary Layer, Turbulence, and Real Gas Effects.

Descriptive Note : Final rept. 1 Jul 92-19 Nov 95,

Corporate Author : WRIGHT LAB WRIGHT-PATTERSON AFB OH

Personal Author(s) : Tolle, Ralph C.

PDF Url : ADA319701

Report Date : OCT 1996

Pagination or Media Count : 271

Abstract : A robust and efficient hypersonic nozzle optimization code is developed and validated. The code is used to redesign an existing axisymmetric Mach 12 wind tunnel nozzle and utilizes response surface methodology (RSM) techniques. In the nozzle optimization, only two variable design parameters are used, along with constraints of fixed nozzle length, throat radius, and exit radius. Explicit, globally second order, flux-difference-splitting algorithms are used to solve the 2-D/axisymmetric Navier-Stokes (NS) and Parabolized Navier-Stokes (PNS) flow solvers incorporated into the optimizer code. Either the Baldwin-Lomax or the Yang-Shih k-epsilon turbulence model may be employed in the nozzle design. The optimization code is developed and validated, and is then used to optimize the Mach 12 nozzle design, and the computed results are compared with those of the original nozzle, the Wright Laboratory Mach 12 wind tunnel nozzle. The code is tested for robustness and on three separate occasions locates the global minimum synonymous with the global best optimized nozzle. The globally optimized nozzle is thus obtained in the two design parameter space, with modest but undesirable disturbances in the inviscid core at the nozzle exit. The RSM techniques used show good promise of greatly facilitating the hypersonic nozzle design process.

Descriptors :   *TURBULENCE, *COMPUTATIONAL FLUID DYNAMICS, *HYPERSONIC WIND TUNNELS, *BOUNDARY LAYER FLOW, MATHEMATICAL MODELS, OPTIMIZATION, AIR FORCE RESEARCH, COMPUTER AIDED DESIGN, TURBULENT FLOW, GAS DYNAMICS, HYDRODYNAMIC CODES, MACH NUMBER, HYPERSONIC CHARACTERISTICS, NAVIER STOKES EQUATIONS, INVISCID FLOW, FREE STREAM, LAMINAR FLOW, HYPERSONIC FLOW, AXISYMMETRIC FLOW, HYPERSONIC NOZZLES.

Subject Categories : Fluid Mechanics
      Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE