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...

Experimentele vortex analysator

A measuring system is described for detection and analyses of aircraft wake vortices in the approach zone of a runway. This system consists of propeller anemometers, a data-acquisition unit, a quick-look monitor and a NOVA minicomputer with a real-time vortex detection program. A short description of aircraft wake vortices is also given. Some...

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...

Results of an improved version of LTRAN2 for computing unsteady airloads on airfoils oscillating in transonic flow

Paper presented at AIAA 12th Fluid and Plasma Dynamics Conference held in Williamsburg, Virginia, 23-26 July 1979. Using an improved version of the NASA Ames code LTRAN2, unsteady airloads were computed for a flat plate and a lifting transonic NACA 6k A006 airfoil, for harmonic pitch and control surface motions at reduced frequencies based on...

MINITWIST: A shortened version of TWIST (Transport WIng STandard Load computer programme)

The Transport Wing Standard programme (TWIST) published in March 1973 is considered to be representative for the load history of the wing root of transport aircraft. A description of the shortened version of this load programme called MINITWIST is given in the present report. In all cases where testing time is a prohibitive factor to use TWIST,...

Processing of Meteosat attitude measurement flight data and evaluation of the performance of an adaptive filtering technique

The attitude measurement data of the ESA geosynchronous spacecraft METEOSAT have been analyzed using an adaptive recursive filtering technique developed at NLR. The mathematical models of spacecraft dynamics and sensors have been kept very simple. Modelling errors are such that, without adaptive feed-back, strong divergence of the filtering...

Computer aided EMC analysis: A review of available tools

A review is given of methods for the analysis of intrasystem electromagnetic compatibility. Emphasis is placed on pocket calculator programs and on the SEMCAP computer program. Taking into account the applications at NLR, we conclude that both tools can be very useful for such an analysis. As far as antenna-to-antenna coupling is considered, the...

Design and analysis of a hodograph method for the calculation of supercritical shock-free aerofoils

In this study, an algorithm for the computational design of supercritical shock-free aerofoils is developed and analyzed with hodograph theory. Such an algorithm may be based on the combination of two approaches for the construction of solutions of the flow equations for shock-free transonic flow. In the first approach, such solutions are...

Computations with the Garabedian and Korn program for two-dimensional transonic flows with embedded shocks

The report describes experiences with the Garabedian and Korn program for the computation of compressible potential flows, with or without shocks, both supercritical shockless flows and flows with shock waves. Computations for a number of quasi-elliptical aerofoils indicated that the conformal mapping procedure should be handled with care....