No description available.

No description available.

A new numerical methodology to examine fluid-structure interaction of a wing/pylon/store system has been developed. The aeroelastic equation of motion of the complete system is solved iteratively in the time domain using a two-entity numerical code comprised of ABAQUS/Standard and the Unsteady-Vortex-Lattice Method. Both codes communicate through an iterative handshake procedure during which displacements and air loads are updated. For each increment in time the force/displacement equilibrium is found in this manner. The wing, pylon, and store data considered in this analysis are based on an F16 configuration that was identified to induce flutter in flight at subsonic speeds. The wing structure is modeled as an elastic plate and pylon and store are rigid bodies. The store body is connected to the pylon through an elastic joint exercising pitch and yaw degrees of freedom. Vortex-Lattice theory featuring closed ring-vortices and continuous vortex shedding to form the wakes is employed to model the aerodynamics of wing, store, and pylon. The methodology was validated against published data demonstrating excellent agreement with documented key phenomena of fluid-structure iteration. The model correctly predicts the effects of the pylon induced lateral flow disruption as well as wing-tip-vortex effects. It can identify the presence of aerodynamic interference between the store, pylon, and wing wakes and examine its significance with respect to the pressure and lift forces on the participating bodies. An elementary flutter study was undertaken to examine the dynamic characteristics of a stiff production pylon at near-critical airspeeds versus those of a soft-in-pitch pylon. The simulation reproduced the stabilizing effect of the stiffness reduction in the pitch motion. This idea is based on the concept of the decoupler pylon, introduced by Reed and Foughner in 1978 and flight tested in the early 1980's. NOTE: (3/07) An updated copy of this ETD was added after there were patron reports of problems with the file. / Ph. D.

In recent years, combat aircraft with external stores have experienced a decrease in their mission capabilities due to lack of robustness of the current passive wing/store flutter suppression system to both structured as well as unstructured uncertainties. The research program proposed here is to investigate the feasibility of using a piezoceramic wafer actuator for active control of store flutter with the goal of producing a robust feedback system that demonstrates increased performance as well as robustness to modeling errors. This approach treats the actuator as an active soft-decoupling tie between the wing and store, thus isolating the wing from store pitch inertia effects. Advanced control techniques are used to assess the nominal performance and robustness of wing/store system to flutter critical uncertainties. NOTE: (10/2009) An updated copy of this ETD was added after there were patron reports of problems with the file. / Ph. D.

No description available.

Master´s thesis deals with design and complex static assessment of steel and timber cable stayed footbridge structural system over the water area. The footbridge is situated into the area of Podyjí National Park near the city of Hnanice. Footbridge span is being used as 52 metres. The structure is formed by flat arched main beams, floor beams, crossbeams, under-deck bracing, pylons and rods. From two variations of footbridge, one was selected and elaborated in more details.

The subject of this master thesis is a design of a bridge for pedestrians and cyclists across the river Morava in Olomouc. Within the scope of thesis there are 3 studies of bridges. Cable-stayed bridge with prestressed spine beam was found appropriate and further calculations were assessed. Static calculations of prestressed spine deck and reinforced concrete pylon were made. Eigen frequencies and modes of construction were obtained. Internal forces were provided by SCIA Engineer with effect of non-linear parameters. Calculations were made according to valid standards and regulations.

The subject of the thesis is to design a suspension footbridge over a river basin. Three different studies were created for the assigned problem. The suspension footbridge was chosen for the thorough elaboration. The most important part of the thesis is the static solution of the supporting structure. The structure model for calculation of impacts of selected strains including the impact of the footbridge construction was created in computational software Ansys. Assessment and dimensioning was carried out using manual calculation according the principles of limit states and applicable standards.

The content of this Master thesis to design installation of hydrogen pressure tanks for airplane VUT RAY 051. Survey was conducted of the available fuel cell on the market. Position of the tank was chosen over the wing using components for mounting a jet engine TJ100 M for aircraft VUT 001 MARABU. For fuel tanks were designed fairings. Further was calculated mass and centre of gravity analysis of aircraft, basic flight performance of aircraft and the drag variation in the location of the tanks above the wing. Further the strain and strength of hinges was calculated.

This diploma thesis deals with the design of a new bridge construction over a multi-lane communication. The converted road is a pedestrian and biking trail connecting significant agglomerations. Three studies were worked out in this thesis and the C variant was selected for further detailed processing. It is an unsymmetrical suspended bridge with a cast-in-place deck. In the section above the communication, the bridge is made up of prefabricated segments. Suspension of the structure is made of two sloping pylons forming a V-shape. The analysis of the construction was carried out in the MIDAS Civil program, where a complete model of construction was entered, including a subsequent estacade. The model describes the construction process and includes creep and shrinkage of the concrete. The traffic, temperature and wind loads were used. The design was assessed for the ultimate limit states and serviceability limit states. The assessment was carried out in the IDEA StatiCa program, supplemented by manual calculations. The static calculations also include assessment of the harmonic response. Subsequently, overview drawings, detailed drawings and visualizations were developed.