Wind tunnel technology for the development of future commercial aircraft

Requirements for new technologies in the area of civil aircraft design are mainly related to the high cost involved in the purchase of modern, fuel saving aircraft. A second important factor is the long term rise in the price of fuel. The demonstration of the benefits of new technologies, as far as these are related to aerodynamics, will,for the foreseeable future, still be based on wind tunnel measurements. Theoretical computation methods are very successfully used in design work, wing optimization, and an estimation of the Reynolds number effect. However, wind tunnel tests are still needed to verify the feasibility of the considered concepts. Along with other costs, the cost for the wind tunnel tests needed for the development of an aircraft is steadily increasing. The present investigation is concerned with the effect of numerical aerodynamics and civil aircraft technology on the development of wind tunnels. Attention is given to the requirements for the wind tunnel, investigative methods, measurement technology, models, and the relation between wind tunnel experiments and theoretical methods

Experimental study of supersonic viscous leeside flow over a slender delta wing

An investigation was conducted to study in detail the vortical flow over the leeward side of a 70 deg swept delta wing having subsonic and supersonic leading edges. Two types of flow were encountered and studied, namely leading edge separation and separation with a shock. Especially for the latter type, Reynolds number plays an important role and unexpected strong streamwise vortices were observed. An optical method is described to obtain a first aproximation of shear stress values in the streamwise direction across the wing span

Lee side flow for slender delta wings of finite thickness

An experimental and theoretical investigation carried out to determine the lee side flow field over delta wings at supersonic speeds is presented. A theoretical method to described the flow field is described, where boundary conditions as a result of the experimental study are needed. The computed flow field with shock induced separation is satisfactory

Leeward flow over delta wings at supersonic speeds

A survey was made of the parameters affecting the development of the leeward symmetric separated flow over slender delta wings immersed in a supersonic stream. The parameters included Mach number, Reynolds number, angle of attack, leading-edge sweep angle, and body cross-sectional shape, such that subsonic and supersonic leading-edge flows are encountered. It was seen that the boundaries between the various flow regimes existing about the leeward surface may conveniently be represented on a diagram with the components of angle of attack and Mach number normal to the leading edge as governing parameters

Fluegel mit kontrollierter Stroemung. Phase I Abschlussbericht

This report describes the technology work carried out under the civil component program ''Wings with Controlled Flow''. Airfoil sections and wings, especially adapted to the use of variable wing camber, were designed and investigated in experiments and theory. The aerodynamic performance advantages of this technology have been demonstrated. The phenomenology of shock-boundary layer interference control was experimentally investigated, and data for a numerical modeling of this effects extracted. The effectiveness of shock-boundary layer interference control was demonstrated on the transonic airfoil and wing design. In addition, numerical problems of laminar/turbulent transition prediction were treated and made available for laminar-flow wing design. A numerical method for the calculation of high-lift configurations (flaps) was developed and verified in detailed experiments. Existing numerical methods were further developed. New measurement techniques were made operational and successfully tested in wind tunnels, in order to support the physical understanding and verify the theoretical development work with measured data. (orig.)SIGLEAvailable from TIB Hannover: RN 5657(121-88) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

Versuchs- und Messtechnik im Hyperschall Zusammenfassung der Vortraege auf der DGLR-Fachausschusssitzung am 02./03.03.1989 in Goettingen

Copy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Design of a Natural Flow Glove for a Transport Aircraft.

After a short description of the national German laminar flow research program, the design of a laminar flow glove on the ATTAS/VFW 614 aircraft of DLR is discussed. This glove is specially designed to allow, by flight testing in combination with stability calculation, the evaluation of limiting N-factors due to Tollmien-Schlichting- and due to crossflow-instability for transition prediction purposes on swept wings. The stability behaviour of the glove is analysed in details

Messtechnik fuer Flugversuche Vortraege

Am 30./31. Januar 1991 fand mit Unterstuetzung durch die Deutsche Airbus GmbH in Hamburg-Finkenwerder eine Fachausschusstagung des DGLR-Fachausschusses FA 3.3 ''Versuchswesen der Fluid- und Thermodynamik'' zum Thema ''Messtechnik fuer Flugversuche'' statt. Die Veranstaltung hatte die Intention, der zunehmenden Bedeutung von Freiflugversuchen und den daraus resultierenden Anforderungen an die Versuchstechnik (z.B. im Bereich der Laminarfluegelforschung) Rechnung zu tragen und einen Erfahrungsaustausch der auf diesem Gebiet arbeitenden Forschungsanstalten, Universitaeten und Industrieunternehmen zu foerdern. Der vorliegende Bericht fasst die auf der FA-Sitzung gehaltenen Vortraege zusammen und gibt damit einen Ueberblick ueber den aktuellen Stand der Entwicklung. (orig./CT)On 30/31st January 1991, a conference of the DGLR specialist committee FA 3.3, ''Experimental fluid dynamics and thermodynamics'', sponsored by German Airbus GmbH, was held on the subject of ''Measurement technology for test flights''. The conference was intended to address the increasing relevance of flight testing and the resulting demands on experimental technology (e.g. in the field of laminar wing research), and offer the opportunity for an information exchange amongst the research institutes, universities and industrial companies working in this field. The following report is a collection of the lectures given at the conference and thus presents an overview of the current status of developments. (orig./CT)SIGLEAvailable from TIB Hannover: RN 3442(256) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Wind tunnel test of over-the-wing nacelles

11 figs.Also published in J. Aircraft v. 20(7) p. 606-611 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman