Comparison of boundary layer calculations for the root section of a wing

At the workshop nine participants presented the results of their calculations for a practical test case. The test case deals with the 3D turbulent boundary layer development, including separation, on the root section of a swept wing. The employed calculation methods comprise 3D integral methods as well as field methods. A short description of...

A system for the numerical simulation of sub- and transonic viscous attached flows around wing-body configurations

A description will be presented of a computer program system that is being used for the prediction of aircraft steady aerodynamic characteristics. Properties of the system are described from two different viewpoints. One is that of the aerodynamic designer, who needs an information system to predict lift, moment and drag characteristics and to...

Application of computational procedures in aerodynamic design

Examples are discussed of the application of computational methods in aerodynamic design problems involving interference. Amongst these are: subsonic wing-body, sting support, pylon-nacelle and pylon-store interference, high-lift devices, induced drag minimization through constrained optimization in the Treftz-plane and transonic wing-fuselage...

A system for computer aided analysis and design of multi-element airfoils

A program system has been developed as a tool for interactive analysis and design of multi-element airfoils in incompressible viscous flow. A global description of the system is given. It involves the application of three computational methods, one for the analysis of viscous flow and one for the analysis of inviscid flow around multi-element...

A survey of numerical methods for the calculation of inviscid, possibly rotational Euler flows around aeronautical configurations

A survey of numerical methods for the calculation of inviscid Euler flows is presented. This survey has been prepared for AGAKD FDP WGOT: "Test cases for steady inviscid transonic or supersonic flows". The survey is augmented by a short assessment of the usefulness of the methods. For aerodynamic applications, the existing methods are in a...

Boundary-layer calculations on the leeward surface of a slender delta wing at incidence

The three dimensional flow field around delta wings with leading-edge vortex flow can be computed with panel methods. However, secondary flow separation may occur on the leeward surface of the wing. The associated free vortex sheet can be modeled in the potential flow calculation method, if the location of the secondary separation is provided by...

On wings and keels

A discussion is given of the physical mechanisms governing the hydrodynamics of sailing yacht keels and the parameters that, through these mechanisms, determine keel performance. It is concluded that due to the presence of the free water surface optimum keel shapes differ from optimum shapes for aircraft wings, a fact that does not seem to have...

A theoretical exploration of the capabilities of 2D flexible wall test sections for 3D testing

The applicability of two-dimensional flexible solid wall test sections for three-dimensional testing is theoretically investigated for linearized subsonic flow. The method uses known interference velocity distributions along a targer line (derived from a method of images for this particular study). From these, wall shapes are calculated that...

A survey of computational methods for subsonic and transonic aerodynamic design

An overview is provided of computational methods that can be used in solving the design problem of aerodynamics; i.e. the problem of finding the detailed shape of (parts of) configurations of which the gross geometric characteristics have already been determined in a preliminary, overall design process, and that, subject to certain constraints,...

3D Euler flow simulations on a cyber 205 vector computer

A computational method for solving the 3D Euler equations is studied. The method is based upon an upwind flux-difference splitting scheme by Osher, exhibiting an implicit mechanism for numerical viscosity, in connection with an explicit time-marching finite-volume technique. The computer program is developed to run efficiently on both a scalar...

A perspective of mathematical simulation and optimization techniques in computer aided design

The central issue discussed in this paper is how a designer may profit from the use of mathematical simulation and optimization techniques. These techniques can be useful tools to support the designer in solving his design problem. The place and the potential of these techniques in the design process, as well as their use by the designer, are...

CAR 88: A method to calculate subsonic and supersonic, steady and unsteady, potential flow about complex configurations

A description is given of the method CAR88 for the calculation of steady and time-linearized unsteady subsonic and supersonic flow about complex 2-D and 3-D configurations. The method belongs to the category of the socalled panel methods. Results of applications in supersonic flow are shown which have been made to a 2-D oscillating flat plate, a...

Computational aerodynamics of ordered vortex flows

The physical aspects, the mathematical modeling, the development and application of computational methods for the simulation of vertical flows are described. The high-Reynolds number vortex flows considered are assumed to be steady, sub-critical and such that the structure of the flow is well-ordered and consists of thin shear layers and slender...

Numerical evaluation of an efficient ROE scheme and chemical models for chemically reacting nozzle flows in thermal equilibrium

An efficient Roe-type flux-difference scheme for chemically reacting inviscid compressible flow in thermal equilibrium is presented. The numerical scheme is validated. Three well known chemical models are compared. The set of testcases concerned quasi one-dimensional hypersonic nozzle flows, with and without strong normal Shockwaves.

De plaats van de wiskundige bij de ontwikkeling van digitale simulatie-systemen voor toepassingen uit de "Computational physics"

NLR mainly performs applied scientific research for use in the aerospace industry. In many cases the product has the form of an information system for the design, production and usage of aerospace vehicles. Within this context, the mathematician contributes, in cooperation with specialists from other disciplines such as aerodynamics, structures,...

Classical HPCN geared to application in industry

In The Netherlands as a result of a national HPCN initiative a Foundation HPCN was established in 1995. The purpose of this Foundation is to stimulate structural and lasting cooperation of universities, technological institutes and industry in economically relevant applications of HPCN. Projects have been selected and since the beginning of 1996...