Conferences, Lectures, & Seminars
Events for November
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AME Department Seminar
Wed, Nov 03, 2010 @ 03:30 PM - 04:30 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Kirk Dotson , Structural Dynamics Department/Structural Mechanics Subdivision
Talk Title: Fluid-Structure Interaction In Launch Vehicle Feedlines During Boost Phase of Flight
Abstract: In structural modeling of launch vehicles, liquid propellant is sometimes rigidly attached to feedline walls. This assumption precludes the interaction of structural modes with propellant pressure and flow. An analysis of fluid-structure interaction (FSI) for the Atlas V launch vehicle revealed that structural models with rigidly-attached propellant yield unconservative response predictions under some conditions. In particular, during the maximum acceleration time of flight, pressure oscillations acting at bends in the Atlas V liquid oxygen feedline excite 15-20 Hz structural modes that have considerable gain on the feedline and at the spacecraft interface. The investigation also revealed that the venting of gas from the pogo accumulator is an excitation source and changes the dynamic characteristics of the hydraulic system. The FSI simulation produced during the investigation can be adapted to mission-specific conditions, such that responses and loads are conservatively predicted for any Atlas V flight.
Host: Professor Geoffrey Speding
More Info: http://ame-www.usc.edu/seminars/11-3-10-dotson.shtmlLocation: John Stauffer Science Lecture Hall (SLH) - , Room 100
Audiences: Everyone Is Invited
Contact: April Mundy
Event Link: http://ame-www.usc.edu/seminars/11-3-10-dotson.shtml
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AME Department Seminar
Wed, Nov 10, 2010 @ 03:30 PM - 04:30 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Marty Bradley, Technical Fellow, The Boeing Company
Talk Title: A Taste of SUGAR (Subsonic Ultra Green Aircraft Research) Results of the Boeing Study for NASA for Future Commercial Aircraft Concepts & Technologies
Abstract: This seminar summarizes the work accomplished by the Boeing Subsonic Ultra Green Aircraft Research (SUGAR) team in a NASA study looking at future concepts and technologies for commercial aircraft in the 2030-2035 timeframe.
The team developed a comprehensive future scenario for world-wide commercial aviation, selected baseline and advanced configurations for detailed study, generated technology suites for each configuration, conducted detailed performance analysis, calculated noise and emissions, assessed technology risks and payoffs, and developed technology roadmaps for key technologies.
Advanced aircraft configurations evaluated in the study included high span strut-braced wings and blended wing bodies (BWB's). A wide portfolio of technologies was identified and evaluated to address the NASA goals. High payoff technologies included hybrid-electric gas turbine battery propulsion, low-NOx combustors, biofuels, advanced air traffic management, noise treatments, laminar flow, and materials.
Compared to today's aircraft, fuel burn reductions of up to 55% were achieved. The additional of hybrid electric propulsion may allow reductions of up to 90%. Significant reductions in emissions, noise, and runway length were also achieved and will be discussed.
Host: Dr. R. Blackwelder
More Info: http://ame-www.usc.edu/seminars/index.shtml#upcomingLocation: John Stauffer Science Lecture Hall (SLH) - 100
Audiences: Everyone Is Invited
Contact: April Mundy
Event Link: http://ame-www.usc.edu/seminars/index.shtml#upcoming
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AME Department Seminar
Wed, Nov 17, 2010 @ 03:30 PM - 04:30 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Jean-Marc Chomaz, Laboratoire d'Hydrodynamique (LadHyX), CNRS-Ecole Polytechnique
Talk Title: The Convective Modoki: The Linear and Nonlinear Dynamics of Real Flows
Abstract: Novel and versatile numerical tolls are used to compute the stability of complex real flows as recirculation bubble, impinging jets, 2D or 3D wakes. Receptivity to perturbation, to blowing and suction, to base flow modification and nonlinear coupling between modes may be accessed by formulating the adjoint problem. Computation of the adjoint global mode show that both the lift-up mechanism associated to the transport of the base flow by the perturbation and the convective nonnormality associated to the transport of the perturbation by the base flow explain the properties of the flow. In particular, a compact wave maker region may be rigorously defined where control will be efficient and nonlinear interaction take place. Application to the nonlinear dynamics of the wake of a disk and of vortex induced vibration will be discussed.
More Info: Dr. G. SpeddingLocation: John Stauffer Science Lecture Hall (SLH) - 100
Audiences: Everyone Is Invited
Contact: April Mundy
Event Link: Dr. G. Spedding
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AME Department Seminar
Fri, Nov 19, 2010 @ 11:00 AM - 12:00 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Ãlisabeth Guazzelli , Associate Professor, IUSTI - CNRS, Polytech'Marseille
Talk Title: Falling Clouds of Particles
Abstract: The time evolution of clouds of particles settling under the action of gravity in an otherwise pure liquid is investigated both experimentally and numerically. It is found that an initially spherical cloud containing enough particles is unstable even in the complete absence of inertia. The cloud slowly evolves into a torus which breaks up into secondary droplets which deform into tori themselves in a repeating cascade. The discrete nature of the particles is fundamental in the understanding of these instabilities. Faster breakup is observed for clouds of anisotropic particles such as fibers due to the self motion of the anisotropic particles. When inertia is finite, the cloud also deforms into a flat torus that eventually destabilizes and breaks up into a number of secondary droplets. While this behavior bears some similarity with that observed at zero-inertia, the underlying physical mechanisms differ. Moreover, the evolution of the cloud deformation is accelerated as inertia is increased. Two inertial regimes where macro-scale inertia and micro-scale inertia become successively dominant are clearly identified.
Host: Dr. E. Kanso
More Info: http://ame-www.usc.edu/seminars/index.shtml#upcomingLocation: Hedco Neurosciences Building (HNB) - 100
Audiences: Everyone Is Invited
Contact: April Mundy
Event Link: http://ame-www.usc.edu/seminars/index.shtml#upcoming