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Technical Paper

“SODART” Telescope Silicon Detector Cooling System (Thermal Test Results of the Scale-Down Model)

The onboard “SODART” telescope silicon detector cooling system of the “Spectrum-X-Gamma” observatory, which is designed for the space objects X-ray radiation study, is described. The scale-down model of the passive cooling system description and thermal vacuum test results of this model are given. In the real cooling system the minimal detector temperature at 300 mW heat release is expected about 107 K.
Technical Paper

eROSITA Camera Low Temperature Thermal Control

eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is a powerful X-ray telescope under development by the Max-Planck-Institut für extraterrestrische Physik (MPE) in Garching, Germany. eROSITA is the core instrument on the Russian SRG1 mission which is planned for launch in 2011. It comprises seven nested Wolter-I grazing incidence telescopes, each equipped with its own CCD camera. The mirror modules have to be maintained at 20°C while the cameras are operated at -80°C. Both, mirrors and CCDs have to be kept within tight limits. The CCD cooling system consists of passive thermal control components only: two radiators, variable conductance heat pipes (VCHP) and two special thermal storage units. The orbit scenario imposes severe challenges on the thermal control system and also on the attitude control system.
Technical Paper

considerations of some JET-DEFLECTION PRINCIPLES for - - directional control - - lift

THE performance characteristics of various devices applicable for jet directional control, lift augmentation, and VTOL-STOL studied at the NACA Lewis Laboratory are discussed, including jet deflection devices applicable to the conventonal round nozzle and novel nozzle configurations. The results indicate that many of the deflection devices applicable to conventional nozzles can readily be used for directional control or lift augmentation. Other deflection devices, such as movable plug, internal flap, cylindrical thrust reverser, swiveled primary with fixed shroud, and 90 deg side-bleed nozzle, are limited in application to jet directional control or aircraft trim because the loss in axial thrust for a given deflection force is prohibitive or the maximum deflected force obtainable is limited.
Technical Paper

byteflight~A new protocol for safety-critical applications

The permanently increasing number of convenience and safety functions leads to higher complexity of in-car electronics and the rapidly growing amount of sensors, actuators and electronic control units places higher demands on high- speed data communication protocols. Safety-critical systems need deterministic protocols with fault-tolerant behavior. The need for on-board diagnosis calls for flexible use of bandwidth and an ever-increasing number of functions necessitates a flexible means of extending the system. None of the communication solutions available on the market until now (like CAN or TTP) have been able to fulfill all these demands. To solve these problems, BMW together with several semiconductor companies has developed a new protocol for safety-critical applications in automotive vehicles.
Technical Paper

Zone of Influence of Porous Suction Tubes in Condensing Heat Exchanger for Space Systems

A “next generation” condensing heat exchanger for space systems has to satisfy demanding operational requirements under variable thermal and moisture loads and reduced gravity conditions. Mathematical models described here are used to investigate transient behavior of wetting and de-wetting dynamics in the binary porous system of porous tubes and porous cold plate. The model is based on the Richard's equation simplified for the zero-gravity conditions. The half-saturation distance or the zone of influence of the porous annular suction tubes on the cold-plate porous material will be in the range of 1 to 10 cm for the time scales ranging from 100 to 10,000 seconds and moisture diffusivity in the range of D = 10-4 to 10-6 m2/s.
Technical Paper

You-Are-Here Maps for International Space Station: Approach and Guidelines

Guidelines for designing you-are-here (YAH) maps aboard International Space Station (ISS) are proposed, based on results from previous 3D spatial navigation studies conducted by our research group and colleagues. This paper reviews terrestrial YAH maps, the common errors associated with them, and how to appropriately implement what is known from terrestrial to micro-gravity YAH maps. We conclude with a creative example of an ISS YAH map that utilizes given guidelines and information visualization techniques.
Technical Paper

XMM-NEWTON Thermal Design and In-orbit Performance

The XMM-NEWTON satellite is the ESA X-ray spaceborne observatory covering the soft X-ray portion of the electromagnetic spectrum. XMM-NEWTON has been put in orbit on December, 10th 1999 by an Ariane 5 single launch. The spacecraft has a conventional thermal design that takes full advantage of the stable environment provided by its high altitude/long period orbit and by the limited variation of solar attitude angles in order to provide a stable platform for the telescope system. The precise geometry and alignment of the telescope system impose strict temperature requirements so that not only temperature gradients have to be kept small but also, and more importantly, time-variations of the gradients have to be minimised. In the paper, the thermal behaviour of the spacecraft as verified by its thermal test programme is compared with the early in-orbit temperature measurements.
Technical Paper

X-Ray Computed Tomography for Verification of Rivet Installation Assessment Techniques

High quality rivet installation is of critical importance to the aerospace industry, and the existence of gaps between the rivet head and the countersink is undesirable. Detection of gaps traditionally involves sectioning through rivet joints. Two concerns exist for this method of evaluation: it provides data only from the sectioned plane, and it has potential to alter the gaps. X-ray computed tomography (CT) was used to validate the effectiveness of the tradition sectioning method. It was revealed that the sectioning process generally increased the size of gaps. CT images also revealed that the gaps are not necessarily uniform around the rivet.

X marks the spot

LiquidPiston Inc. has developed a new engine that can run on multiple fuels, including diesel, jet fuel, and gasoline. This platform uses an optimized thermodynamic cycle and a new rotary engine architecture and could increases flight endurance over conventional UAV engines by greater than 50%.
Technical Paper

Workspace Analysis and Visualization for Santos'™ Upper Extremity

Workspace is an important function for human factors analysis and is widely applied in product design, manufacturing, and ergonomics evaluations. This paper presents the workspace analysis and visualization for Santos™ upper extremity, a new virtual human with over 100 DOFs that is highly realistic in terms of appearance, behavior, and movement. Jacobian Rank deficiency method is implemented to determine the singular surfaces. The joint limits are considered in this formulation; three types of singularities are analyzed. This closed-form formulation can be extended to numerous different scenarios such as different percentiles, age groups, or segments of body. A realtime scheme is used to build the workspace library for Santos™ that will study the boundary surfaces off-line and apply them to Santos™ in the virtual environment (Virtools®). To visualize the workspace, we develop a user interface to generate the cross section of the reach envelope with a plane.

Wire and Cable Marking Process, UV Laser

This standard is applicable to the marking of aerospace vehicle electrical wires and cables using ultraviolet (UV) lasers. This standard specifies the process requirements for the implementation of UV laser marking of aerospace electrical wire and cable and fiber optic cable to achieve an acceptable quality mark using equipment designed for UV laser marking of identification codes on aerospace wire and cable. Wiring specified as UV laser markable subject to AS4373 and which has been marked in accordance with this standard will conform to the requirements of AS50881.

Wire and Cable Marking Process, UV Laser

This standard is applicable to the marking of aerospace vehicle electrical wires and cables using ultraviolet (UV) lasers. This standard specifies the process requirements for the implementation of UV laser marking of aerospace electrical wire and cable and fiber optic cable to achieve an acceptable quality mark using equipment designed for UV laser marking of identification codes on aerospace wire and cable. Wiring specified as UV laser markable subject to AS4373 Test Methods for Insulated Electric Wire and which has been marked in accordance with this standard will conform to the requirements of AS50881.
Technical Paper

Wind-Tunnel Investigation of the Forebody Aerodynamics of a Vortex-Lift Fighter Configuration at High Angles of Attack

Results of a recent low-speed wind-tunnel investigation conducted to define the forebody flow on a 16% scale model of the NASA High Angle-of-Attack Research Vehicle (HARV), an F-18 configuration, are presented with analysis. Measurements include force and moment data, oil-flow visualizations, and surface pressure data taken at angles of attack near and above maximum lift (36° to 52°) at a Reynolds number of one million based on mean aerodynamic chord. The results presented identify the key flow-field features on the forebody including the wing-body strake.
Technical Paper

Wind Tunnel Measurements of Simulated Glaciated Cloud Conditions to Evaluate Newly Developed 2D Imaging Probes

Instrumentation that has been used for characterization of mixed-phase and glaciated conditions in the past, like the OAP probes, are subject to errors caused by variations in diffraction on the images away from the object plane and by the discrete nature of their particle detection and sizing. Correction methods are necessary to consider their measurements adequate for high ice water content (IWC) environments judged to represent a significant safety hazard to propellers and turbofan engine operability and performance. For this reason, within the frame of EU FP7 HAIC project, instrumentation characterization and validation is considered a major element need for successful execution of flight tests campaigns. Clearly, instrumentation must be sufficiently reliable to assess the reproducibility of artificial clouds with high ice water content generated in icing tunnels.
Technical Paper

Wick Characterization by Image Analysis

The microstructure characterization of tubular wicks is discussed using an image analysis method, mercury intrusion porosimetry and Arquimedes method. The central objective of this work is to determine the wide convenience of the image analysis technique for wick characterization. It is demonstrate that the image analysis technique is an appropriate tool to determine correlation function, total porosity and pore size distribution in two-dimensional (2-D) binary images of microstructures. The correlation function is used to simulate the 3-D reconstruction of porous structure. The images were obtained from a set of wick samples made of sintered nickel, through scanning electronic microscopy (SEM). A computer program (Imago) was developed and used in the work. The mercury intrusion porosimetry is also used to provide information about the breakthrough diameter of porous material. Results show porosity of about 60% and effective pore size less than 4 μm.
Technical Paper

Welding With a High-Power CO2 Laser

The application of a production-oriented high-power CO2 laser system for the welding of auto underbody components is reported. Sheet metal sections, varying in thickness from 0.060-0.135 in, are welded at speeds up to 500 in/min at 6 kW. An overview of recent developments in laser welding is presented along with a discussion of the laser deep-penetration weld phenomenon. A comparison is made between laser and electron-beam welding performance.