ADAS structures module: Evaluation report

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 ...

User's manual for the computer program CUFUS: Quick design procedure for a CUt-out in a FUSelage version 1.0

Worst case gust shapes for atmospheric turbulence with known spectrum

A worst case gust shape has been derived for turbulence or gust patches, assuming only that the average spectrum of such patches is known. The maximum value of the response can be calculated quite easily. The result differs from the PSD-method. Some examples of worst case inputs and outputs are given, also for nonlinear systems.

The deterministic power-spectral-density-method for nonlinear systems

The Deterministic Power-Spectral-Density method can be derived from the Design Envelope Analysis of the continuous P.S.D.-method. It provides a method to determine a deterministic function that gives a maximum response equal to the P.S.D.-design load for linear systems. The P.S.D.-design load is undefined for nonlinear systems. In this report a ...

The deterministic power-spectral-density-method for linear systems

The Deterministic Power-Spectral-Density-method has been derived directly from the continuous P.S.D.-method. It can be regarded as a "translation" from the frequency domain to the space or time domain. The critical gust profile, giving maximum response, is obtained directly. The D.P.S.D.-method gives the same results as the continuous P.S.D.-...

Rekenprogramma's voor het ontwerpen en dimensioneren van vezelversterkte kunststoffen

This report provides an inventory of computer programs for composite materials which are owned by or known to the members of the NFK-TVK action group. The programs are divided in four groups: general laminate theory; specific laminate problems; general (F.E.) analysis programs; miscellaneous problems. The programs are not discussed in the report...

Definition of P.S.D.-design loads for nonlinear aircraft

The Power Spectral Density (P.S.D.)-method is used to define design loads due to atmospheric turbulence. The design loads are calculated using linear transfer functions. These methods can not be used if the equations describing the behaviour of the aircraft are nonlinear. One method to define design loads for a nonlinear aircraft is by means of...

Standardized environmental fatigue sequence for the evaluation of composite components in combat aircraft (ENSTAFF = ENvironmental FalSTAFF)

Fatigue life assessment of composite structures in fighter aircraft necessitates testing with both mechanical and environmental loading at both coupon and structural element size levels. Testing facilities to run such tests are now available but environmental fatigue testing is expensive and time consuming. An environmental fatigue loading...

How to generate equal probability design load conditions

This report gives an outline of the method to generate equal probility design load conditions. The various steps are described.

A CAD-system for the design of stiffened panels in wing box structures

In this paper the CAD system DESTIP is described. DESTIP is developed at the NLR for designing compression panels in wing box structures. Application of the system yields optimal panels in the sense that they meet all the requirements imposed by the designer and have minimum weight per unit width. Weight reductions ranging from 0 to 10% have...

Simulation and optimization techniques in computer aided design

The use of numerical simulation and optimization techniques is rapidly expanding in all fields of engineering design. The place and the potential of these techniques in the design process, as well as their use by the designer, are discussed. The principles underlying these techniques are outlined and an overall view is given of the various...

An introductory course on aircraft loading

The present course book has been prepared as lecture notes for a summer course given at the Technical University of Bandung (ITB) in the summer of 1984. This course took place within the framework of the TTA-79 Technical Assistance Project as agreed between the Governments of Indonesia and the Netherlands. The subjects of the course are listed...

Review and comparison of discrete and continuous gust methods for the determination of airplane design loads

Historical reviews of the discrete gust and the continious gust concept, in relation to the present requirements, are given in this report. A comparison is made between the discrete gust method and the power spectral density method on the basis of simple airplane models. No direct relation between the two methods exists. The main cause of the...

Operating conditions and materials selection and development in gas turbines

This paper consists of two parts. In the first part, concerning operational conditions in gas turbines, the following topics are covered: - the magnitude of temperatures, temperature profiles, and stresses in various components - transient temperature conditions, occuring as a result of e.g. throttle setting changes and affecting thermal fatigue...