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Our previously reported steady-state thermal analysis for a rolling passenger tire has been modified. This makes possible a nonsteady-state thermal analysis for tires which operate under nonsteady-state conditions. A finite element analysis was used which involved the solution of a set of simultaneous heat balance equations. Conduction within the tire, conduction to the road surface, convection to the contained air and to the surrounding air, and radiation from the outside and inside surfaces of the tire were taken into account. The experimentally measured infrared surface temperature distribution was used as input data. A new, fast-response infrared camera and infrared recorder were used to obtain the data. The results gave, as a function of time, the complete temperature distribution and rates of heat generation in the tire.

The nature of close air support and its operational criteria are defined, together with resultant aircraft design requirements. It is shown that the proper approach toward evaluation of the cost effectiveness of a close support aircraft requires examination of acquisition costs, maintenance and operations costs, aircraft responsiveness, effectiveness, and vulnerability, and that evaluation on the basis of payload and range alone can produce incorrect conclusions. The Northrop F-5 tactical fighter is examined for its close support capabilities. It is concluded that, because of the original design approach, the F-5 meets all close support fighter aircraft requirements.

A recently developed aerodynamic loss analysis tool is helping engineers better understand loss mechanisms and compare turbomachinery redesign concepts; these loss analysis calculations are based on GE-Aircraft Engine's Computational Fluid Dynamics (CFD) simulations. The loss analysis tool, ENPROD3D, computes the thermodynamic parameter “Entropy Production” based on flux balance calculations. As an example, GEAE's E3 High Pressure Turbine Stage 1 Blade, has been analyzed using ENPROD3D; nearly half the total entropy produced is a result of boundary layer shear, 1/3 of the entropy production is a result of trailing edge wake-related aerodynamic losses, and the remainder loss is charged to secondary flow.

The projected uptick in world passenger traffic challenges the involved stakeholders to optimise the current aviation system and to find new solutions being able to cope with this trend. Since especially large hub airports are congested, operate at their capacity limit and further extensions are difficult to realise. Delays due to late arrival of aircraft or less predictable ground operation processes disrupt the airport operations in a serious way. Various concepts improving the current turnaround processes have been presented thus far, whereby radical aircraft design changes have little chances for realisation in the short term. By maintaining the established overall aircraft configuration, the concepts promote higher probability to become commercially available for aircraft manufactures and operators.

The FAA and other Air Navigation Service Providers (ANSPs) plan to share the existing cockpit data radio for NextGen data communication applications. This radio is currently used for supporting airline operations. Sharing this radio, which operates in a relatively open network environment, with mission critical air traffic control communications creates a need to address air-ground security. Most of the data to be shared over air-ground communication is tactical and transient in nature. In addition, secure communication between the controller and the pilot provides situational awareness to all receivers listening on the voice radio channel. In this paper we provide a rationale for securing air-ground communication and explore some of the issues in implementing a secure air-ground communication channel between the controller and the pilot over the shared radio.

This paper focuses on the design, construction, preliminary testing, and potential applications of three forms of miniaturized analytical instrumentation. The first is an optical fiber instrument for monitoring pH and other cations in aqueous solutions. The instrument couples chemically selective indicators that have been immobilized at porous polymeric films with a hardware package that provides the excitation light source, required optical components, and detection and data processing hardware. The second is a new form of a piezoelectric mass sensor. The sensor was fabricated by the deposition of a thin (5.5 μm) film of piezoelectric aluminum nitride (AlN). The completed deposition process yields a thin film resonator (TFR) that is shaped as a 400 μm square and supports a standing bulk acoustic wave in a longitudinal mode at frequencies of ∼1 GHz.

The Closed Equilibrated Biological Aquatic System (C.E.B.A.S.) is a man-made aquatic ecosystem which typically consists of an aquatic animal habitat, an aquatic plant bioreactor, an ammonia oxidizing bacteria filter and a data acquisition/control unit. It is a precursor for different types of fish and aquatic plant production sites suitable for integration into bioregenerative life support systems. The results of two successful spaceflights of a miniaturized C.E.B.A.S version (the C.E.B.A.S. MINI MODULE) allow the optimization of aquatic food production systems which are already developed in the ground laboratory and open new aspects for their utilization as aquatic modules in space bioregenerative life support systems.

This paper presents a demonstrator developed in the European CleanSky2 project MISSION (Modelling and Simulation Tools for Systems Integration on Aircraft). Its scope is the development towards a seamless integrated, interconnected toolchain enabling more efficient processes with less rework time in todays, highly collaborative aerospace domain design applications. The demonstration described here, consists of an open, modular and multitool platform implementation, using specific techniques to achieve fully traceable (early stage) requirements verification by virtual testing. The most promising approach is a model based integration along the whole process from requirements definition to the verified, integrated (and certified) system. Extending previous publications in this series, the paper introduces the motivation and briefly describes the technical background and a potential implementation of a workflow suitable for that target.

We present a framework for the robust optimization of the heat flux distribution for an anti-ice electro-thermal ice protection system (AI-ETIPS) and iced airfoil performance analysis under uncertain conditions. The considered uncertainty regards a lack of knowledge concerning the characteristics of the cloud i.e. the liquid water content and the median volume diameter of water droplets, and the accuracy of measuring devices i.e., the static temperature probe, uncertain parameters are modeled as uniform random variables. A forward uncertainty propagation analysis is carried out using a Monte Carlo approach. The optimization framework relies on a gradient-free algorithm (Mesh Adaptive Direct Search) and three different problem formulations are considered in this work. Two bi-objective deterministic optimizations aim to minimize power consumption and either minimize ice formations or the iced airfoil drag coefficient.

Maintaining a healthy atmosphere in closed life support systems is essential for the crew well being and the success of manned space missions. During the SBIR Phase I effort, Lynntech, Inc., developed a bench scale trace contaminant control (TCC) system utilizing a photocatalytic filter. Testing successfully demonstrated the technology feasibility for eliminating airborne chemicals and microorganisms. During the SBIR Phase II project, a scaled-up, fully operational breadboard system is being developed and tested. Testing gases include chemicals significantly present in the International Space Station cabin air and that are drivers in the design of trace contaminant control systems. The use of Lynntech’s air cleaner allows for a system that is cost-effective and functional with a superior removal of gas pollutants and bio-aerosols from contaminated air streams beyond the capabilities of traditional photocatalysis. It also overcomes limitations of current TCC systems.

This paper offers a concept for a regenerable, low-power system for purifying exhaust from a solid waste processor. The innovations in the concept include the use of a closed-loop regeneration cycle for the adsorber, which prevents contaminants from reaching the breathable air before they are destroyed, and the use of a humidity-swing desorption cycle, which uses less power than a thermal desorption cycle and requires no venting of air and water to space vacuum or planetary atmosphere. The process would also serve well as a trace contaminant control system for the air in the closed environment. A systems-level design is presented that shows how both the exhaust and air purification tasks could be performed by one processor. Data measured with a fixed-bed apparatus demonstrate the effects of the humidity swing on regeneration of the adsorbent.

Monitoring the quality of astronaut potable and hygiene water is one of the highest priorities of a regenerative life support system for manned space missions to the ISS, Moon, Mars, and other remote locations. Real-time monitoring allows analysis of water processing from wastewater to potable water and would enable the rapid diagnosis and correction of a processing failure if a water-related health issue were to arise. Among detectors used to monitor recycled water quality, a total organic carbon (TOC) instrument or its functional equivalent should be used to assess the organic contaminant level. Through the NASA Small Business Innovative Research (SBIR) program, Lynntech has developed a novel, mesofluidic Total Organic Carbon Analyzer (TOCA) for real-time monitoring of water quality. It has been designed for an operational lifetime of 5 years with no maintenance required and no need to supply reagents or water.

During the 1930s and 1940s, aircraft designers worked on developing novel design features. Some of these features worked and are commonplace today. Other features fell by the wayside and have been forgotten. These novel design features include laminar flow wings, low-drag cooling systems, buried propulsion systems, canard configurations, jet engines, break-away wing tips, pressure cabins and swept wings. The development and applications of these features will be examined. Specific technical details of these applications will be included in this examination. For the design features that fell by the wayside, the reasons for this outcome will be discussed

An investigation was performed to evaluate a novel and inexpensive wind tunnel model mount for dynamic aerodynamic testing. A computer analysis code was developed to identify the dimensions of the control surface needed to produce a desired pitching motion for a delta wing. The code was then used to design and build a dynamic model apparatus that was evaluated in a low speed wind tunnel at Wichita State University. The dynamic model mount and control were evaluated for a variety of motions, including constant pitch rate ramps, constant frequency oscillations and impulse or step inputs. Results from the ramp and oscillation test indicated the system is very responsive and capable of a wide range of motion.

Cloud properties retrieved from satellite data are used to diagnose aircraft icing threat in single layer and multilayered ice-over-liquid clouds. The algorithms are being applied in real time to the Geostationary Operational Environmental Satellite (GOES) data over the CONUS with multilayer data available over the eastern CONUS. METEOSAT data are also used to retrieve icing conditions over western Europe. The icing algorithm's methodology and validation are discussed along with future enhancements and plans. The icing risk product is available in image and digital formats on NASA Langley ‘s Cloud and Radiation Products web site, http://www-angler.larc.nasa.gov.

A discussion of wing-nozzle configuration development for the application of upper surface blowing to a STOL airplane is presented. The technical challenge is to achieve an integrated system which provides the desired performance for the low speed design conditions and also results in efficient operation during cruise. The resulting configuration is a complete integration of the propulsion system and airplane aerodynamics to achieve efficient operation at all regimes. This paper examines the major design parameters to be considered, describes a number of the configurations tested, and presents static and wind tunnel test results for these configurations. Concluding remarks are made relative to USB nozzle development.

A radioisotope-fueled thermoelectric generator is ideally suited to the nighttime power requirements of unmanned soft lunar landing experiments. A generator design capable of producing 25 w of electric power as well as sufficient thermal energy for environmental control of critical electronic components is described. Sufficient curium-242 may be encapsulated to provide an operational life of 90-120 days in a unit weighing 30 lb. This unit will extend the data gathering capability of the experiment with a significant weight advantage over conventional power supplies.

This work establishes and describes a new nuclear electric propulsion technology category for achieving a much lower system alpha in future space transport vehicles to significantly reduce transit time to Mars and other deep space science mission destinations. The new power conversion technology combines the Brayton cycle with a thermoacoustic Stirling cycle into a Closed Strayton Quad Generator that significantly increases the efficiency, specific power, and maximum turbine inlet temperature while insuring high reliability and long-life operation. A proposed design of this power conversion system is presented along with a performance and mass comparison to current state of practice.

The success of the development of nuclear thermal propulsion devices and thermionic space nuclear power generation systems depends on the successful utilization of nuclear fuel materials at temperatures in the range 2000 to 3500 K. Problems associated with the utilization of uranium bearing fuel materials at these very high temperatures while maintaining them in the solid state for the required operating times are addressed. The critical issues addressed include evaporation, melting, reactor neutron spectrum, high temperature chemical stability, fabrication, fission induced swelling, fission product release, high temperature creep, thermal shock resistance, and fuel density, both mass and fissile atom. Candidate fuel materials for this temperature range are based on UO2 or uranium carbides. Evaporation suppression, such as a sealed cladding, is required for either fuel base.

This paper addresses nuclear hardness assurance as it relate to system acquisition, prerequisite efforts necessary for an affordable hardness assurance program, and the key aspects of the management of the program.