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This specification covers established metric manufacturing tolerances applicable to aluminum alloy drawn tubing ordered to metric dimensions. These tolerances apply to all conditions, unless otherwise noted. The term "excl" applies only to the higher figure of the specified range.

This specification covers established metric manufacturing tolerances applicable to aluminum alloy drawn tubing ordered to metric dimensions. These tolerances apply to all conditions, unless otherwise noted. The term "excl" applies only to the higher figure of the specified range.

The Manufacturing Message Specification is an application layer Standard designed to support messaging communications to and from programmable devices in a Computer Integrated Manufacturing (CIM) environment. This environment is referred to in this Standard as the manufacturing environment. This Standard does not specify a complete set of services for remote programming of devices, although provision of such a set of services may be the subject of future standardization efforts.

“Spotlight on Design: Insight” features an in-depth look at the latest technology breakthroughs impacting mobility. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing cost, improving quality, safety or environmental impact, and achieving regulatory compliance. As global concerns about the negative consequences of greenhouse gases on the environment increase, regulatory agencies around the world are taking serious steps to address the issue of tailpipe emissions In the episode “Fuel Efficiency: Fuel Economy Testing” (12:05), engineers at the EPA’s National Vehicle and Fuel Emissions Laboratory demonstrate how different vehicles are tested for emissions, and AVL’s technical team shows how accurate tailpipe emissions can be measured and reported.

This technical paper collection features 15 papers covering electrification of the commercial vehicle, techniques for efficiency and reliability; developments in sensors; model based design and embedded software development; heavy duty electronic technology; autonomous vehicles; electronic control module development and test; and vehicle structure.

The collection features 19 technical papers covering power electronics, generators, motors, power conversion, power distribution, power management and related power utilization areas related to commercial aircraft and unmanned vehicles electrical power generation, power management/power distribution, control & protection corona and arc fault detection, power conversion/conditioning, fuel cells, energy storage – batteries/ultracapacitors, and other related issues. The collection features 19 technical papers covering power electronics, generators, motors, power conversion, power distribution, power management and related power utilization areas related to commercial aircraft and unmanned vehicles electrical power generation, power management/power distribution, control & protection corona and arc fault detection, power conversion/conditioning, fuel cells, energy storage – batteries/ultracapacitors, and other related issues.

This collection features 9 technical papers describing the progress in new engine concepts relating to both airbreathing and non-airbreathing configurations. This collection features 9 technical papers describing the progress in new engine concepts relating to both airbreathing and non-airbreathing configurations.

This SAE Aerospace Information Report (AIR) describes procedures, required continuous sampling conditions, and instrumentation for the measurement of non-volatile particle number and mass concentrations from the exhaust of aircraft gas turbine engines. Procedures are included to calculate sampling loss performance. This AIR is not intended for in-flight testing, nor does it apply to engine operating in the afterburning mode.

This Aerospace Information Report (AIR) is a historical technical record describing procedures, required continuous sampling conditions, and instrumentation for the measurement of non-volatile particle number and mass concentrations from the exhaust of aircraft gas turbine engines. Procedures are included to calculate sampling loss performance. This AIR is not intended for in-flight testing, nor does it apply to engine operating in the afterburning mode. This Aerospace Information Report is a historical technical record of the initial document detailing the measurement of non-volatile particle emissions at the exit plane of aircraft gas turbine engines. This methodology was adopted by ICAO into Annex 16 Vol II and updated into Aerospace Recommended Practice ARP6320. Future updates of this document may include explanations of the reasoning and assumptions used to develop this measurement methodology.

This document establishes the minimum criteria for effective training of air carrier and contractor personnel to deice/anti-ice aircraft to ensure the safe operation of aircraft during ground icing conditions. Appendix D specifies guidelines for particular airplane models.

This set includes: SAE International Journal of Aerospace March 2010 - Volume 2 Issue 1 SAE International Journal of Commercial Vehicles October 2009 - Volume 2, Issue 1 March 2010 - Volume 2, Issue 2 SAE International Journal of Engines October 2009 - Volume 2, Issue 1 March 2010 - Volume 2, Issue 2 SAE International Journal of Fuels and Lubricants October 2009 - Volume 2, Issue 1 March 2010 - Volume 2, Issue 2 SAE International Journal of Materials and Manufacturing October 2009 - Volume 2, Issue 1 March 2010 - Volume 2, Issue 2 SAE International Journal of Passenger Cars - Electronic and Electrical Systems October 2009 - Volume 2, Issue 1 SAE International Journal of Passenger Cars - Mechanical Systems October 2009 - Volume 2, Issue 1 March 2010 - Volume 2, Issue 2

Abstract More than a decade ago, we proposed combined use of direct injection (DI) and jet ignition (JI) to produce high efficiency, high power-density, positive-ignition (PI), lean burn stratified, internal combustion engines (ICEs). Adopting this concept, the latest FIA F1 engines, which are electrically assisted, turbocharged, directly injected, jet ignited, gasoline engines and work lean stratified in a highly boosted environment, have delivered peak power fuel conversion efficiencies well above 46%, with specific power densities more than 340 kW/liter. The concept, further evolved, is here presented for unmanned aerial vehicle (UAV) applications. Results of simulations for a new DI JI ICE with rotary valve, being super-turbocharged and having gasoline or methanol as working fuel, show the opportunity to achieve even larger power densities, up to 430 kW/liter, while delivering a near-constant torque and, consequently, a nearly linear power curve over a wide range of speeds.

Abstract This study discusses the experimental investigation on WEDM of combustor material (i.e., nimonic 263). Experimentation has been executed by varying pulse-on time (Ton), pulse-off time (Toff), peak current (Ip), and spark gap voltage (Sv). Material removal rate (MRR), surface roughness (SR), and wire wear rate (WWR) are employed as process performance characteristics. Experiments are designed as per the box-Behnken design technique. Parametric optimization has also been performed using response surface methodology. Besides this, field-emission scanning electron microscope (FE-SEM) and an optical microscope are utilized to characterize WEDMed and worn-out wire surfaces. It is observed that both surfaces contain micro-cracks, craters, spherical droplets, and a lump of debris. Furthermore, the mechanism of recast layer formation has been critically evaluated to apprehend a better understanding of the technique. The key features of the experimental procedure are also highlighted.

Abstract While the design of nozzles for diatomic gases is very well established and covered by published works, the case of a diatomic gas dissociating to monatomic along a nozzle is a novel subject that needs a proper mathematical description. These novel studies are relevant to the definition of nozzles for gas-core Nuclear Thermal Rockets (NTR) that are receiving increased attention for the potential advantages they may deliver versus current generation rockets. The article thus reviews the design of the nozzles of gas-core NTR that use hydrogen as the propellant. Propellant temperatures are expected to reach 9,000-15,000 K. Above 1500 K, hydrogen begins to dissociate at low pressures, and around 3000 K dissociation also occurs at high pressures. At a given temperature, the lower the gas pressure the more molecules dissociate, and H2 → H + H. The properties of the gas are a function of the mass fractions of diatomic and monatomic hydrogen x H2 and x H = 1 − x H2.

Abstract Constant area section length downstream to the fuel injection point is a crucial dimension of scramjet duct geometry. It has a major contribution in creating the maximum effective pressure inside the combustor that is required for propulsion. The length is limited by the thermal choking phenomenon, which occurs when heat is added in a flow through constant area duct. As per theory, to avoid thermal choking the constant area section length depends upon the inlet conditions and the rate of heat addition. The complexity related to mixing and combustion process inside the supersonic stream makes it difficult to predict the rate of heat addition and in turn the length. Recent efforts of simulating the reacting flow inside scramjet combustors are encouraging and can be useful in this regard. The presented work attempts to use simulation results of scramjet combustion for predicting the constant area section length for a typical scramjet combustor.

Abstract Jet engine hot parts (e.g., jet nozzle) are a crucial source of aircraft’s infrared (IR) signature from the rearview, in 1.9-2.9 μm and 3-5 μm bands. The exhaust nozzle design used in a jet aircraft affects its performance and IR signature (which is also affected just by performance) from the engine layout. For supersonic aircraft (typically for M ∞ > 1.5), a converging-diverging (C-D) nozzle is preferred over a convergent nozzle for optimum performance. The diverging section of the C-D nozzle has a full range of visibility from the rearview; hence, it was not considered a prudent choice for low IR observability. This theoretical study compares the IR signature of the C-D nozzle with that of the convergent nozzle from the rearview in 1.9-2.9 μm and 3-5 μm bands for the same thrust.

Abstract The preliminary gas turbine combustor design process uses a huge amount of empirical correlations to achieve more optimized designs. Combustion efficiency, in relation to the basic dimensions of the combustor, is one of the most critical performance parameters. In this study, semi-empirical correlations for combustion efficiencies are examined and correlation coefficients have been revised using an experimental air-blasted tubular combustor that uses JP8 kerosene aviation fuel. Besides, droplet diameter and effective evaporation constant parameters have been investigated for different operating conditions. In the study, it is observed that increased air velocity significantly improves the atomization process and decreases droplet diameters, while increasing the mass flow rate has a positive effect on the atomization—the relative air velocity in the air-blast atomizer increases and the fuel droplets become finer.