Searched for: subject%3A%22method%22
(1 - 20 of 82)

Pages

document
Schepers, J.G. (author), Oerlemans, S. (author), Guidati, G. (author), Wagner, S. (author)
The objective of the European project DATA (Design and Testing of Acoustically Optimized Airfoils for Wind Turbines) is a reduction of trailing-edge (TE) noise by modifying the airfoil shape and/or the application of trailing-edge serrations. This paper describes validation measurements that were performed in the DNW-LLF wind tunnel, on a model...
report 2001
document
de Koning, A.U. (author), Henriksen, T.K. (author)
Probably one of the most challenging problems in fracture mechanics is related to its application to fastener and joints. By nature, not only the quality such as material, manufacturing and mounting processes, of the fasteners are playing a role, but also the stiffness, surface conditions and geometry of the parts are to be considered. Moreover,...
report 1996
document
Arendsen, P. (author), van Dalen, F. (author), Bill, C. (author), Rothwell, A. (author)
In a joint research project between the National Aerospace Laboratory (NLR) and the Faculty of Aerospace Engineering of Delft University of Technology (TUD) a multi-level system for the preliminary design of aircraft structures has been developed. The present system is essentially an extension of the existing Aircraft Design and Analysis System ...
report 1995
document
van Rijn, J.C.N. (author)
The stress distribution in the vicinity of a notch is investigated as a first step towards a more fundamental understanding of the blunt notch behaviour of fibre metal laminates. The applicability of several analytical methodologies for determination of the stress distribution in the vicinity of a notch in a finite width plate is assessed in...
report 1994
document
Ellenbroek, M.H.M. (author), de Boer, A. (author)
Fokker Space and Systems and the National Aerospace Laboratory NLR performed a study to integrate more systematically the experimental and analytical analysis of the dynamic behaviour of structures. The study focused on the correlation of experimental and analytical data, matrix and parameter updating methods. In this paper an overview will be...
report 1993
document
Hoeijmakers, H.W.M. (author)
An analysis is presented of results of a computational method to simulate the steady compressible vortical type of flow around a 65-deg sharp-edged cropped delta wing. The discussion emphasizes some more fundamental aspects of the numerical simulation such as the separation of the flow, the structure of the leading-edge vortex core and the flow...
report 1991
document
't Hart, W.G.J. (author)
The susceptibility of currently used CFRP to impact damage has stimulated the development of improved composites. This new generation of composites usually shows increased toughness and damage tolerance as well as improved tensile performance. This is generally not matched, however, by a similar improvement in compressive properties which then...
report 1991
document
Moek, G. (author)
In this report, the application of estimation theory to three problems from aerospace research is described. The applications considered deal with spacecraft attitude estimation, software reliability modelling and estimation, and with a satellite-based navigation algorithm. Maximum likelihood estimation is used in the software reliability case...
report 1991
document
Roos, N. (author)
In this thesis, which consists of two parts, two different subjects are discussed. In the first part of the thesis a logic for reasoning with inconsistent knowledge will be described. The second part of the thesis contains a proposal for to view a reasoning process as a process of constructing a partial model of the world we are reasoning about....
report 1991
document
Hounjet, M.H.L. (author)
A method is presented for the generation of 0-type grids about transverse cross-sections of transport type aircraft. The method combines a hyperbolic grid generation scheme with source terms obtained with a boundary element method in such a way that 0-type grids around fairly complex shapes with concavities can be generated easily. The...
report 1990
document
ten Dam, A.A. (author)
A mathematical theory for modelling dynamical systems with equality state-space constraints is presented. The dynamic behaviour of these systems is represented by a combination of differential and algebraic equations. It Is shown that the freedom offered by control is essential to obtain other, mathematically equivalent formulations. The notion...
report 1990
document
van der Vooren, J. (author), van der Wees, A.J. (author)
The mathematical background is described of a method that is currently being developed at NLR to calculated wave drag in transonic potential flow. The method is a generalization and extension of Garabedian's and McFadden's idea of determining wave drag by volume-integration of the artificial viscosity. The generalization of Garabedian's and...
report 1990
document
de Boer, A. (author), Ellenbroek, M.H.M. (author)
A description is given of the second problem, a clamped-free truss structure, defined in the GARTEUR Action Group 11. The measured and calculated modal data of the structure are correlated, the locations of the errors are determined and finally the finite element model of the structure is updated. These analyses are performed with the B2000...
report 1990
document
Spekreijse, S.P. (author), Venis, A.C.J. (author)
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.
report 1990
document
ten Dam, A.A. (author)
Numerical simulation of constrained dynamical systems is known to exhibit stability problems even when the unconstrained system can be simulated in a stable manner. We show that not the constraints themselves, but the transformation of a continuous set of equations to a discrete set of equations is the true source of the stability problem....
report 1990
document
ten Dam, A.A. (author), Dieleman, P. (author)
This report describes the results of an evaluation of numerical integration schemes to be used for the digital simulation of second order ordinary differential equations (ODE's) which are characteristic for multibody systems such as space manipulators. The study focuses on dedicated schemes for this type of systems. Main attention is paid to the...
report 1990
document
Hoeijmakers, H.W.M. (author)
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...
report 1989
document
Laméris, J. (author), Minderhoud, P. (author)
The mechanical behaviour of mechanically fastened double lap carbon-epoxy joints has been investigated both by experiments (static tests) and by analysis. Several fastener types and joint geometries has been investigated. In the experimental programme the Fibredux 6376/T400H material was used. Two methods to analyze mechanically fastened...
report 1989
document
Riks, E. (author), Merazzi, S. (author), de Boer, A. (author)
In many practical problems of plate and shell buckling, the pre-buckling state is linear and can be obtained from the linearized equations of elasticity. The computation of the buckling load and mode in such cases correponds to a linear eigenvalue problem that can easily be formulated and implemented in a finite element code. This report...
report 1988
document
Hounjet, M.H.L. (author)
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...
report 1988
Searched for: subject%3A%22method%22
(1 - 20 of 82)

Pages