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Predicting the aerodynamic performance of an aircraft in icing conditions is critical as failures in an aircraft’s ice protection system can compromise flight safety. Aerodynamic effects of icing have typically relied on RANS modeling, which usually struggles to predict stall behavior, including those induced by surface roughness. Encouraged by recent studies using LES that demonstrate the ability to predict stall characteristics on full aircraft with smooth wings at an affordable cost [1], this study seeks to apply this methodology to icing conditions. Measurements of lift, drag, and pitching moments of a NACA23012 airfoil under clean and iced conditions are collected at Re = 1.8M. Using laser scanned, detailed representations of the icing geometries, LES calculations are conducted to compare integrated loads against experimental measurements in both clean and iced conditions at various angles of attack through the onset of stall [2].

Measurements from a Global Navigation System in conjunction with an Inertial Measurement Unit were recently introduced in different aerial and ground vehicles as an input to control vehicle dynamics. In automobiles this approach could help to further improve braking and / or stability control systems as information like velocity over ground and side slip angle becomes available. This paper presents the technical background, validation through test results and the evaluation of potential benefits of such an “INS/GPS” setup. As a result of the extended measuring capabilities a reduction in braking distance and a more effective stability control becomes possible. The results show an excellent performance that should be exploited in future automotive applications.

This paper describes the computational results of the flow field around two vehicle geometries using the Immersed Boundary (IB) technique in conjunction with a steady RANS CFD solver. The IB approach allows the computation of the flow around objects without requiring the grid lines to be aligned with the body surfaces. In the IB approach instead of specifying body boundary conditions, a body force is introduced in the governing equations to model the effect of the presence of an object on the flow. This approach reduces the time necessary for meshing and allows utilization of more efficient and fast CFD solvers. The simulations are carried out for an SUV and a pickup truck models at a Reynolds number of 8×105. Cartesian meshes (non-uniform) with local grid refinement are used to increase the resolution close to the boundaries. The simulation results are compared with the existing measurements in terms of surface pressures, velocity profiles, and drag coefficients.

The Rotating Disk Analytical System (R-DAS) is an in-situ, bio-analytical technology, which utilizes a micro-fluidic disk with similar form factor as an audio compact disc to enhance and augment microgravity-based cellular and molecular biology research. The current micro-fluidic assay performs live cell/dead cell analysis using fluorescent microscopy. Image acquisition and analysis are performed for each of the selected microscope slide windows. All images are stored for later download and possible further post analysis. The flight version of the R-DAS will occupy a double mid-deck shuttle locker or one quarter of an ISS rack. The control system for the R-DAS consists of a set of interactive software components. These components interact with one another to control disk rotation, vertical and horizontal stage motion, sample incubation, image acquisition and analysis, and human interface.

Hybrid electric vehicles are seen as a solution to improving fuel economy and reducing pollution emissions from automobiles. By recovering kinetic energy during braking and optimizing the engine operation to reduce fuel consumption and emissions, a hybrid vehicle can outperform a traditional vehicle. In designing a hybrid vehicle, the task of finding optimal component sizes and an appropriate control strategy is key to achieving maximum fuel economy. In this paper we introduce the application of convex optimization to hybrid vehicle optimization. This technique allows analysis of the propulsion system's capabilities independent of any specific control law.

Development of a suitable EVA suit for use on Mars will be a significant technological challenge. A particular concern is the excessive weight of existing planetary spacesuit designs. Mars has approximately one-third of the Earth's gravitational pull. Therefore, heavy suits will significantly hamper effective EVA operations. A suit design investigated by research groups from Stanford University and U.C. Berkeley uses semi-permeable membranes as a passive thermal control system. This design replaces the bulky active thermal control systems in more traditional spacesuit designs by working with the natural thermal control mechanisms of the human body. This idea is only possible due to the unique Martian atmosphere and the normal way in which the human body regulates its own temperature via sensory feedback to the brain, sweat, and regulation of blood flow.

Several recent papers describe closed loop fuel-air ratio control systems designed to operate at stoichiometric conditions because of the high three-way catalyst conversion efficiencies which occur only in a narrow band around stoichiometric. This paper investigates closed loop control of fuel-air ratio using a temperature compensated zirconia sensor at other than stoichiometric conditions. If engines can be made to run at very lean(Φ≈0.6-0.7) equivalence ratios through greater attention to proper fuel-air mixing and vaporization, CO, HC, and NOx emissions are minimized simultaneously. Closed loop control in the lean region makes the system insensitive to parameter variations and allows the fuel-air ratio to be maintained closer to the lean limit than would be possible under conventional open loop conditions.