Downloads & Free Reading Options - Results

Probabilistic methods have been implemented with a computational fluid dynamics simulation of fluid flow and heat transfer in a gas turbine engine. The simulation models the temperatures in the T-56 series III 1-2 spacer. Three input quantities are treated as random variables. A random sampling method is used to generate the input values from a probability density function. The implemented Monte Carlo method uses a large number of samples of the input variables to calculate results repeatedly for the output variables (i.e. the predicted temperatures). Statistics of the predicted temperatures, such as the mean and variance, are then calculated. The variation in the predicted temperature at one point in the turbine of the T56 engine is seen to be more sensitive to variability in some parameters than in others.

Three dimensional, steady-state, laminar, fully viscous Navier-Stokes simulations were used to predict the behavior of incompressible liquids that were undergoing steady spin and steady precession at a fixed precession angle. These numerical simulations can predict steady viscous and pressure moments. These moments tend to increase the precession angle and reduce the spin rate of the container system. For a completely filled cylinder, liquid-induced roll and side (yaw) moments were computed as functions of cylinder height to diameter. Keywords: Finite difference, Incompressible flow, Liquid-filled projectile, Liquid moment, Low reynolds number, Rotating liquids.

The research reported herein addresses the reduced basis method, which is based on the combination of a basic iteractive method and a projection method. The convergence is analyzed and some error bounds are established. The relationship between the reduced basis method and the preconditioned conjugate gradient method is discussed. Also included is a practical implementation of the reduced basis method when a pseudoresidual-based Krylov space is chosen. The final section of this report dwells on the weight selection procedures of hybrid difference methods for the linear convective equation. The procedures are based on the ability of hybrid difference methods to conserve the discrete weighted energy. Keywords: Reduced basis; Linear solver; Contraction number; Projection method; Sparse symmetric linear systems; Hybrid difference methods.

High-order space-time methods for Computational Fluid Dynamics are studied. Both explicit and implicit schemes will be discussed

Popular high-order schemes with compact stencils for Computational Fluid Dynamics (CFD) include Discontinuous Galerkin (DG), Spectral Difference (SD), and Spectral Volume (SV) methods. The recently proposed Flux Reconstruction (FR) approach or Correction Procedure using Reconstruction (CPR) is based on a differential formulation and provides a unifying framework for these high-order schemes. Here we present a brief review of recent developments for the FR/CPR schemes as well as some pacing items.

Includes bibliographical references (p. [353]-361) and index

The papers presented at the AGARD Fluid Dynamics Panel Specialists' Meeting on 'Computational Methods for Aerodynamic Design (Inverse) and Optimization' are reviewed. Strengths and weaknesses are identified for many of the contributions as each is reviewed. The reviewer closes with some general comments. The 23 papers presented at the Meeting have been collected in AGARD CP 463 (ADA220870). Keywords: Computer aided design; Computational fluid dynamics; Inverse methods; Aerodynamic characteristics/optimization.

The papers presented at the AGARD Fluid Dynamics Panel Specialists' Meeting on 'Computational Methods for Aerodynamic Design (Inverse) and Optimization' are reviewed. Strengths and weaknesses are identified for many of the contributions as each is reviewed. The reviewer closes with some general comments. The 23 papers presented at the Meeting have been collected in AGARD CP 463 (ADA220870). Keywords: Computer aided design; Computational fluid dynamics; Inverse methods; Aerodynamic characteristics/optimization.

Dynamic mesh adaptation strategies are investigated. These include software development, dynamically adaptive mesh schemes, errors arising from generalized mappings and orthogonality. The strategies developed are tested against the euler and viscous Burgers Equations.