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The aim of this work is to apply an innovative adaptive ℒ1 techniques to control flutter phenomena affecting highly flexible wings and to evaluate the efficiency of this control algorithm and architecture by performing the following tasks: i) adaptation and analysis of an existing simplified nonlinear plunging/pitching 2D aeroelastic model accounting for structural nonlinearities and a quasi-steady aerodynamics capable of describing flutter and post-flutter limit cycle oscillations, ii) implement the ℒ1 adaptive control on the developed aeroelastic system to perform initial control testing and evaluate the sensitivity to system parameters, and iii) perform model validation and calibration by comparing the performance of the proposed control strategy with an adaptive back-stepping algorithm. The effectiveness and robustness of the ℒ1 adaptive control in flutter and post-flutter suppression is demonstrated.

A Web-based version of the aircraft design program ACSYNT has been created. “Web-ACSYNT” provides the user with a familiar user interface and is accessible from multiple platforms. Analyses are based upon a set of baseline aircraft models which can be modified through a carefully selected set of parameters related to weight, aerodynamics, propulsion, economics, and mission. The software is intended to become one of the models that comprise the Aviation System Analysis Capability (ASAC) currently being developed by NASA under the Advanced Subsonic Technology (AST) program.

An unique bonding mechanism was studied after several instances, where the linings stuck to the brake drums on transit buses, were reported. Evidences suggested that the linings were “glued” to the brake drums surface after wear debris (dust) was turned into “adhesive paste” through complicated thermal and chemical changes. Factors such as the friction materials, environment and service conditions, which could activate and deactivate the lining bonding, were observed and discussed. The prevention measures are proposed.

Proper lubrication of moving parts is a critical factor in internal combustion engine performance and longevity. Determination of ideal lubricant change intervals is a prerequisite to ensuring maximum engine efficiency and useful life. When oil change intervals are pushed too far, increased engine wear and even engine damage can result. On the other hand, premature oil changes are inconvenient, add to vehicle maintenance cost, and result in wasted natural resources. In order to determine the appropriate oil change interval, we have developed an oil condition sensor that measures the electrical properties of engine oil, and correlates these electrical properties to the physical and chemical properties of oil. This paper provides a brief background discussion of the oil degradation process, followed by a description of the sensor operational principles and the correlation of the sensor output with physical and chemical engine oil properties.

This paper presents, chemistry, test data and processing procedures on a non toxic and environmentally friendly chrome-free conversion coating alternative with the same level of adhesion and secondary corrosion resistance as that found in chrome containing conversion coating systems. Test data from military and independent sources will be presented on secondary coating adhesion, electrical conductivity, filiform and neutral salt-spray corrosion resistance as compared to chromate based systems .on magnesium, aluminum and zinc and their respective alloys. The European “RoSH” initiative will not allow for the presence of any hexavalent chromium on imported electrical components as of July first of 2006. Trivalent chromium based systems generate hexavalent chromium due to the oxidation of the trivalent chromium and as such will not be allowed.

MONOGAL is a coated steel developped to improve the corrosion resistance of exposed automotive body applications. Its process os based on the brittleness of the η zinc coating in a range of temperatures below the melting point of the zinc. MONOGAL is produced on a hot dip galvanizing line; at the exit of the pot the free zinc is brushed off the light side of the differentially coated sheet. Side 1 of MONOGAL presents a very thin and continuous layer of iron-zinc diffusion alloy with no free zinc. Side 2 is a standard G90 or G60 zinc coating. The iron-zinc alloy layer has excellent anti-galling properties which improve the formability of MONOGAL over two side hot dip galvanized steel with the same r value. MONOGAL also shows good weldability, paintability and corrosion resistance.

Affordable, efficient and durable catalytic converters for the two and three wheeler industry in developing countries are required to reduce vehicle emissions and to participate in a cleaner and healthier environment. As a contribution Continental Emitec started a comprehensive testing program with a state of the art 180 cc Bharat Stage (BS) III Indian motorcycle. The program consists of testing the state of the art of Metallic substrates with structured foils with various catalyst sizes and positions (original or close coupled). The publication presents a short literature survey and the results of the investigation with a big catalyst volume mounted in underfloor position as well as in close coupled position, gained over the World-wide harmonized Motorcycle Test Cycle, considering the two possible vehicle classifications of this motorcycle, Sub-Class 2.1 and Sub-Class 2.2.

Energy demand climbs as a consequence of the inherent relationship between the rate of consumption of energy and the growth of the economy. In light of the depletion of fossil fuels, it is necessary to implement energy efficiency techniques and policies that support sustainable development. Globally, researchers show more interest in discovering fossil fuel alternatives, as a result of fuel crisis. This research elaborates on the production and experimental investigation of briquettes made from ideal municipal solid waste (MSW), such as food waste and garden waste, as a feasible choice for alternate fossil fuels. From Municipal, agricultural, and food waste, we can get biomass waste. Municipal solid and agricultural waste is extensively dispersed, but their potential for converting biomass into energy generation still needs to be explored. This study was carried out based on the information gathered from various studies published in the scientific literature.

This paper presents the derivation of the equations for circumferential, longitudinal and radial heat transfer conductance for a thin shell toroid or a segment of the toroid. A thin shell toroid is one in which the radius to thickness ratio is greater than 10. The equations for the surface area of a toroid or of a toroidal segment will also be derived along with the equation to determine the location of the centroid. The surface area is needed to determine the radial conductance in the toroid or toroidal segment and the centroid is needed to determine the heat transfer center of the toroid or toroidal segment for circumferential and longitudinal conductance. These equations can be used to obtain more accurate results for conductive heat transfer in toroid which is a curved spacecraft components. A comparison will be made (1) using the equations derived in this paper which takes into account the curvature of the toroid (true geometry) and (2) using flat plates to simulate the toroid.

“DELRIN” is a new thermoplastic which offers high strength, excellent thermal stability, good fatigue life, low creep, and excellent solvent resistance. This paper describes the physical and chemical properties of the material, and the range of possible uses. The material is easily fabricated into complex shapes by standard injection-molding techniques. Also, it can be easily joined to itself or to other materials. The authors think that the material offers advantages over metals in its good fric-tional properties, abrasion resistance, and corrosion resistance.

The objective of the development of the aerodynamic drag predictive tool CDaero was for use as a module for the Automobile Design Support System (AutoDSS). CDaero is an empirically based drag coefficient predictive tool based initially on the MIRA (Motor Industry Research Association) algorithm. The development philosophy was to be able to predict the aerodynamic drag coefficient of an automobile with knowledge of the features of the surface geometry control curves. These are the curves that control the 3-dimensional geometry as seen in the profile, plan and front and rear views. CDaero has been developed in a computing environment using the equation solver TKSolver™. Fifty-one input feature values are first determined from the automobile geometry and then entered into the program. CDaero models the drag coefficient with thirteen different components covering the basic body, as well as additional components such as the wheels, mud flaps, etc.

Whether we live on land, underwater, or out there in space, what makes it possible is our ‘skin’. The one we were born with, the one we wear, the one we live in, and the one we travel in. The skin is a response to where we live: it protects as our first line of defense against a hostile environment; it regulates as part of our life-support system; and, it communicates as our interface to everything within and without. In the context of space architecture – we, our space suits, vehicles and habitats are all equipped with highly specialized ‘skins’ that pad us, protect us and become an integral part of the design expression. This paper approaches the subject from a holistic perspective considering ‘skins’ and their manifestation as structure, as vessel, as texture, and as membrane. The paper then goes on to showcase innovative use of materials in practice through two case studies: the ‘spacesuit’ and ‘inflatable habitats’.

This specification covers the characteristics of glass beads used for peening, and provides for standard glass bead size numbers.

This specification covers the characteristics of glass beads used for peening, and provides for standard glass bead size numbers.

3-D Flow separations such as those that occur on the rear end of a vehicle have an impact on wall pressure distribution, hence on aerodynamic forces. The identification of these phenomena can be made through the analysis of skin friction patterns, which consist of the “footprints” of flow separations. These can be determined from qualitative and quantitative data obtained from near-wall PIV measurements. The wake flow of different configurations of a simplified 1/4 scale car model are analyzed. The influence of the slant angle and the Reynolds number on 3-D separated flow patterns and their induced pressure distribution is addressed, based on near-wall PIV, standard PIV and wall pressure measurements. This enables to understand how a topological change (the size or shape of a separation pattern) modifies the associated pressure distribution (therefore the drag coefficient). Finally, insights into instantaneous topology identification are presented.

RADIOTRACERS were used to study the wear effects of engine speed, load, jacket water temperature, fuel temperature, and chromium-plated rings in a medium-speed diesel engine. One distillate fuel and two residual fuels were tested. This paper describes the tests and their results. Some of the conclusions are: The brake thermal efficiency with high viscosity residual fuel was essentially equal to distillate diesel fuel over a wide range of loads, providing the residual fuel was heated to the proper temperature. Engine speed did not affect the wear rate of cast-iron rings when distillate fuel was used, while with residual fuel wear decreased with increased speed. With distillate fuel, engine load had essentially no effect on cast-iron ring wear. With residual fuel, decreasing engine load produced a marked increase in ring wear*

TWO TYPES of bench wear tests employed by the General Motors Research Laboratories are described, and examples are given to illustrate the application of the tests to material development problems. It is shown that correlation of a bench test with service may be achieved even when the laboratory test conditions do not appear to duplicate service conditions exactly. It is postulated that this behaviour is related to the formation of certain types of surface films during the wearing process. Some preliminary results are given of a study of the influence of lubricant type and material composition on the formation of anti-wear films.

THIS PAPER REPORTS on the present state of the art in the utilization of refractory metals for air frame and powerplant sheet metal components. By far the most promising of these metals to date is molybdenum. The mechanical and physical properties of molybdenum are well-suited for high-temperature service. The combination of relatively high thermal conductivity, low thermal expansion coefficient, good specific heat, and a reasonably high emissivity of a coated surface make this material suitable for exterior surface application on severely aerodynamically heated components. However, in its usable alloyed forms, molybdenum tends to behave in a brittle manner at room temperature, suffering from a high brittle-to-ductile transition temperature. Other unacceptable properties are the presence of laminations in the material, 45-deg preferred angle cracking, and difficulty of controlling interstitial alloying elements. The authors discuss each of these and the progress made in overcoming them