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Widening of the A1 motorway between Köln‐Niehl and Leverkusen‐West – general planning of the motorway segment and design of the bridge over the Rhine River in Leverkusen The existing bridge over the Rhine River in Leverkusen is reaching its limit due to heavy load traffic having increased enormously since the 1960s. The replacement of the bridge over the Rhine River and the predicted future traffic volume require the widening of the A1 motorway segment between the Köln‐Niehl junction and the Leverkusen‐West interchange to eight continuous traffic lanes. For the first time in Germany, a cable‐stayed bridge over the Rhine River needs to be replaced. The construction of a new twelve‐lane bridge over the Rhine River while maintaining traffic on the six traffic lanes of the existing bridge goes hand in hand with the widening of the approx. 4.55 km motorway segment containing a total of 15 bridges, retaining walls, basin systems, noise barriers and traffic sign structures. A single general planner is responsible for nearly the entire planning of this construction project. Only surveying and landscape architecture services are provided by the client. The widening of the motorway and the replacement of the engineering structures within the secured former Dhünnaue landfill site represent a particular challenge. Efficient emission protection measures are to be provided for the work inside the landfill site. The site must be resealed, and the drainage and ventilation system connecting to the new traffic infrastructure and engineering structures must be restored. [ABSTRACT FROM AUTHOR]

The Fröschnitz 1 and Fröschnitz 2 supply shafts of the Semmering Base Tunnel are used for the ventilation of the tunnel drives, transport of personnel, materials and machinery and as escape and rescue routes. Until the final completion of the concrete inner lining in the shafts, water still emerges repeatedly at the surface at a few locations of the shotcrete support layer. This led above all for the Fröschnitz 2 shaft to ice formation during longer periods with outside air temperatures below the freezing point of water with simultaneous operation of the fresh air supply. The effectiveness of warm air supply was investigated with thermodynamic and aerodynamic investigations and then the cost‐effectiveness of two selected systems to provide warm air were considered. The aerodynamic simulations showed that in particular the entry angle of the warm fresh air flow is decisive for the magnitude of the warm air losses. [ABSTRACT FROM AUTHOR]

Bionik of flight feathers Large soaring landbirds depend on cross-country flights as cheaply as possible. The migration of eastern European White Storks to southerly wintering areas with a length of more than 8000 km as well as the foraging flights of vultures over huge areas are physiologically only possible thanks to optimized soaring flight capabilities of the birds. The mechanisms to increase uplift and to reduce unwanted friction and vortex drags as presented here show that these adaptations are realized down to the microstructural level of the flight feathers. These are in particular: the airstream permeable structures along the feather shaft, the flow adaptive curvature of the feather profile and the shaping of the feather tip. These mechanisms serve a significant reduction of drag which was prerequisite to a successful development of the flight feather cascade. In conferred form they can be found also in technical missiles. [ABSTRACT FROM AUTHOR]

Bis zum Ausbruch des Ersten Weltkrieges gab es kaum eine deutsche Großstadt, die nicht bereits über eine Luftschiffhalle verfügte oder über deren Errichtung nachdachte - wollte sie nicht den Anschluss an das prophezeite Luftschiff-Verkehrsnetz verpassen. Die starren Gerüstluftschiffe des Zeppelin-Typs setzten sich zunehmend durch, stellten aber besondere Anforderungen. Das Eigengewicht ihrer Konstruktion verlangte ein viel größeres Gasvolumen und erforderte Luftschiffhallen mit immensen Ausmaßen. Nach jedem Fahrtende war ihre Verbringung in Bergehallen unbedingt erforderlich. Das Ein- und Aushallen der Luftschiffe, vor allem das Passieren der Tore bei Seitenwind, blieb immer ein kritischer Moment. Zur Lösung dieses Problems wurden elektrisch in den Wind drehbare Luftschiffhallen favorisiert [1]. Solche Drehhallen waren ungleich teurer. Als Kompromiss wurden Luftschiffhallen fest in Hauptwindrichtung gebaut und deren Tore zumeist als Windschutzwände ausgebildet. Bis Kriegsende wurde nicht von glattwandigen, abstehenden Toren abgewichen, obwohl dies mehrfach für Unfälle sorgte. Da viele Luftschiffhäfen gleichzeitig Flugplätze waren, machte sich der störende Einfluss der kantigen Luftschiffhallen-Baukörper auf die laminare Strömung besonders bemerkbar und erzeugte Wirbel, die den leichten Flugapparaten wie auch den Luftschiffen bei Bodenmanövern gleichermaßen gefährlich wurden. Die Ausnahme bildete ein allseits abgerundeter Luftschiffhallentyp, der 1913 in Dresden, Liegnitz und Posen errichtet wurde - Konstruktionen eines heute unbekannten Ingenieurs: Ernst Meier (Bild 1). Seine Erfindung des Kuppeldrehtores ermöglichte erstmals auch die sphärische Wölbung der beiden Hallengiebelseiten. Geöffnet schmiegten sich die Torhälften zudem so an den Hallenkörper an, dass im Torbereich kaum Strömungsbehinderung stattfand und die kritischen Luftwirbel ausblieben. Erst nach dem Ersten Weltkrieg und durch den kriegsbedingt gewachsenen Wissensstand in der Strömungsmechanik wurde dieser Vorteil allgemein anerkannt und weltweit auf eine Vielzahl Luftschiffhallen und -hallenentwürfe angewandt [2]. [ABSTRACT FROM AUTHOR]

Das Markgräfler Brauchtum des Scheibenschlagens zur Fasnachtszeit ist nicht nur ein traditionelles Spektakel; es lässt sich auch physikalisch untermauern. Wie hoch sind Startgeschwindigkeit und Startimpuls der Scheibe? Wie wirkt sie als Flugkörper und wie stabilisiert sie ihren Flug? Strömungsmechanische Messungen an Originalscheiben geben darüber Auskunft. [ABSTRACT FROM AUTHOR]

In the present paper experimental aerodynamic investigations on an airship configuration at angle of attack with special emphasis on the hull-fin region are reported. In particular, visualizations of flow phenomena on both hull and fins are studied. Quantitative measurements of the integral force and moment characteristics as well as local pressure coefficients serve to establish a data pool for code validation. [Copyright &y& Elsevier]

Due to a trend towards very high-bypass ratio engines and a corresponding close coupling of engine and airframe, the minimization of adverse interference effects is an important aspect in aircraft design. Investigations of engine/airframe integration have been carried out within a long-term collaborative European research initiative, starting in 1990 with the programs DUPRIN I, DUPRIN II to the current ENIFAIR and AIRDATA projects. Based on some selected results the contribution highlights major outcomes of the numerical activities accompanying the experimental studies in the aforementioned programs. After a brief introduction to the basic aerodynamic phenomena of engine/airframe interference and the numerical methods in use, the capabilities of the theoretical approach are demonstrated for three aspects: The influence of increasing engine size on the aerodynamic interference is outlined by simulating turbine powered engine simulators (TPS) of different bypass ratio on the ALVAST narrow body wing/fuselage model. Second, the influence of position variations is demonstrated for different engine concepts, representing the major design parameter for influencing engine/airframe interference. Finally, the jet influence is stressed by comparing numerical results for different thrust conditions. The investigations show, that the lift loss, caused by the mounting of engines, is proportional to the engine size. An upstream movement of the engine position alleviates the lift loss, whereas a vertical movement does not have a significant influence. Especially for the VHBR and UHBR concepts the incorporation of the engine jet is essential to assess the aerodynamic interference. In general validated numerical methods are capable to simulate the dominant features of engine/airframe integration. [Copyright &y& Elsevier]