330 research outputs found
Information Switching Processor (ISP) contention analysis and control
Future satellite communications, as a viable means of communications and an alternative to terrestrial networks, demand flexibility and low end-user cost. On-board switching/processing satellites potentially provide these features, allowing flexible interconnection among multiple spot beams, direct to the user communications services using very small aperture terminals (VSAT's), independent uplink and downlink access/transmission system designs optimized to user's traffic requirements, efficient TDM downlink transmission, and better link performance. A flexible switching system on the satellite in conjunction with low-cost user terminals will likely benefit future satellite network users
Effect of Pivot Point on Aerodynamic Force and Vortical Structure of Pitching Flat Plate Wings
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106512/1/AIAA2013-792.pd
Aerothermodynamic Optimization of Hypersonic Vehicle TPS Design by POD/RSM-Based Approach
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76303/1/AIAA-2006-777-653.pd
Three-Dimensional Adaptive Grid Computation with Conservative, Marker-Based Tracking for Interfacial Fluid Dynamics
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76614/1/AIAA-2006-1523-676.pd
Interesting magnetic properties of FeCoSi alloys
Solid solution between nonmagnetic narrow gap semiconductor FeSi and
diamagnetic semi-metal CoSi gives rise to interesting metallic alloys with
long-range helical magnetic ordering, for a wide range of intermediate
concentration. We report various interesting magnetic properties of these
alloys, including low temperature re-entrant spin-glass like behaviour and a
novel inverted magnetic hysteresis loop. Role of Dzyaloshinski-Moriya
interaction in the magnetic response of these non-centrosymmetric alloys is
discussed.Comment: 11 pages and 3 figure
Effects of Reynolds Number and Flapping Kinematics on Hovering Aerodynamics
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76695/1/AIAA-2007-129-236.pd
Poisson -- Boltzmann Brownian Dynamics of Charged Colloids in Suspension
We describe a method to simulate the dynamics of charged colloidal particles
suspended in a liquid containing dissociated ions and salt ions. Regimes of
prime current interest are those of large volume fraction of colloids, highly
charged particles and low salt concentrations. A description which is tractable
under these conditions is obtained by treating the small dissociated and salt
ions as continuous fields, while keeping the colloidal macroions as discrete
particles. For each spatial configuration of the macroions, the electrostatic
potential arising from all charges in the system is determined by solving the
nonlinear Poisson--Boltzmann equation. From the electrostatic potential, the
forces acting on the macroions are calculated and used in a Brownian dynamics
simulation to obtain the motion of the latter. The method is validated by
comparison to known results in a parameter regime where the effective
interaction between the macroions is of a pairwise Yukawa form
Aerodynamics of Pitching Wings: Theory and Experiments
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140444/1/6.2014-2881.pd
Computational Fluid-Structure Interaction of a Deformable Flapping Wing for Micro Air Vehicle Applications
Motivated by micro air vehicle applications, a fluid-structure coupling procedure between a Navier- Stokes solver and a three-dimensional FEM beam solver is presented along with selected results highlighting some of the aerodynamics implications. The fluid model includes laminar, the k -ε turbulence closure, and a filter-based k -ε closure. The structural model is based on an asymptotic approximation to the equations of elasticity. Using the slenderness as the small parameter, the equations are decomposed into two independent variational problems, corresponding to (i) crosssectional, small-deformation and (ii) longitudinal, large deformation analyses. A model example problem corresponding to a NACA0012 wing of aspect ratio 3 in pure heave motion is presented and the results compared against available experiment data. Quantitative comparisons with experiment are done for the rigid wing and the implications of wing flexibility on aerodynamics are presented in a qualitative sense. It was observed that phase lag of the wing tip displacement relative to the flapping motion becomes more pronounced as the fluid density increases. Copyright © 2008 by the American Institute of Aeronautics and Astronautics, Inc.Published versio
Investigation of the Unsteady Aerodynamics of Insect Flight:The Use of Immersed Boundary Method
- …