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Vehicle aerodynamic development, drag reduction and fuel economy, handling and stability, cooling flows, surface soiling and water management, vehicle internal environment, tyre aerodynamics and modelling, aeroacoustics, structural response to aerodynamic loading, simulating the on-road environment, onset flow turbulence, unsteady aerodynamics, fundamental flow structures, new test methods and facilities, new applications of computational fluid dynamics simulation, competition vehicle aerodynamics.

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 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 The range of an aircraft is determined by the amount of energy that its batteries can store. Today, larger batteries are used to increase the range of electric vehicles, although energy efficiency decreases as the weight of the vehicles increases. Among the elements, lithium (Li) is the lightest and has the highest electrochemical potential. Therefore, the use of Li-ion batteries is recommended for hybrid aircraft. In addition, Li-ion batteries are the most common type of battery that is used in portable electronic devices such as smartphones, tablets, and laptops. However, Li-ion batteries may explode due to temperature. Therefore, the thermal analysis of Li-ion batteries was investigated both experimentally and numerically. Li-ion batteries were connected in series (the number is 9). Noboru’s theory of heat generation was discussed in the estimation of energy data.

Abstract Inline piston pumps are extensively used in aircraft hydraulic systems. They can be found in engine-driven large-sized hydraulic pumps and zonal electric motor-driven mid-small sized pumps. Inline piston pumps are positive displacement pumps with variable volumetric flow controls. Positive displacement pumps can provide a variable flow rate over a wide range of suction pressures. Aircraft fly at high altitudes, and therefore these pumps have to work in extreme conditions such as low atmospheric pressure, low temperature. At low inlet pressures, the pump is highly susceptible to cavitation, i.e., insufficient filling capacity. The pressure below which pump flow rate drops drastically is known as critical inlet pressure. Extensive research has been carried out to study cavitation in inline piston pumps.

Vehicle aerodynamic development, drag reduction and fuel economy, handling and stability, cooling flows, surface soiling and water management, vehicle internal environment, tyre aerodynamics and modelling, aeroacoustics, structural response to aerodynamic loading, simulating the on-road environment, onset flow turbulence, unsteady aerodynamics, fundamental flow structures, new test methods and facilities, new applications of computational fluid dynamics simulation, competition vehicle aerodynamics.

The scope of this document is to provide a guidance of the common contamination types and their concentrations in order to size FTIS components and characterize its performance on generic commercial aircraft.

Aircraft-mounted Closed Circuit Refueling receiver adapter – Definition of standard interface dimensions for adapter which interfaces with MIL-PRF-52747F Nozzle.

This SAE Aerospace Recommended Practice (ARP) provides guidance for the verification and certification of a “commercial” fixed wing aircraft fuel tank inerting system (FTIS) and will provide technical references and data regarding ground and flight testing of an FTIS. The intent of this ARP is to address issues associated with the verification requirements based on current regulatory guidance per AC25.981-2C

The document provides a definition of skew and disconnect occuring in high lift systems in flight controls including their hazard assessment, describes generic solutions and provides a for specifying requirements.

Scope: This Aerospace Recommended Practice (ARP) provides guidelines for specifying dielectric withstanding strength and insulation resistance design and test requirements for aircraft line replaceable units (LRU's) used within a flight control and/or a utility system. 1.1 Purpose The testing is intended to verify that an LRU can operate safely at its rated voltage and withstand momentary over potentials due to switching, troubleshooting testing, surges, etc.. The testing is also intended to verify adequate design margin of the insulation system and detect workmanship problems.

This Aerospace Recommended Practice (ARP) offers guidelines for specifying servoloop pressure feedback transducers for use in hydraulic actuation for servosystems.

Aeroengine Hazard Zone document will standardize the major aspects of processes that may be used for the determination of hazards to aerospace personnel when performing duties on turbojet, turbofan, turboprop and auxiliary power units installed on aircraft. It includes discussions of basic definitions, analytical and methods to describe the hazard zones for a given propulsion system installed on various aircraft. Standardization of definitions of sources of hazards, tools, presentation of hazard zones would benefit airplane, engine, airline customers and airport planners.

To cover all forms of equipment used to inject/blend additive into the fuel flowing from the refueling equipment to the aircraft. For any additive, injected by any means. We plan 4 basic types of equipment from fully manual to fully automatic.

This Aerospace Recommended Practice (ARP) provides guidance on methods for system level pump ripple and pulsation testing. Covered are pump testing versus system pulsation testing, test conditions, instrumentation and data collection, data reduction and analysis, and resolution of issues identified during testing.

This specification covers a high-temperature, electrical grade, polyimide resin adhesive in the form of film or paste.

This specification covers a high-humidity-resistant, modified epoxy adhesive in the form of film.

This specification covers a high-humidity-resistant, modified epoxy adhesive in the form of film supplied as rolls or sheets.

This specification covers a high-humidity-resistant, modified epoxy adhesive in the form of film supplied as rolls or sheets.

This specification covers a high-temperature, electrical-grade, polyimide resin adhesive in the form of film or paste.