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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.

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.

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.

An Airbus methodology for the assessment of accurate fuel pressure surge at early program stages in the complete aircraft and engine environment based on joint collaboration with LMS Engineering is presented. The aim is to comfort the prediction of the fuel pressure spike generated by an engine shutdown in order to avoid late airframe fuel system redesign and secure the aircraft entry-into-service.

Air to Air refueling (AAR) operations are typically performed with dedicated tanker A/C. Most existing tankers are derived from civil airliners like the A330MRTT from Airbus Military or from military transport A/C with permanent modifications for the tanker role. For being able to refuel in flight some type of receivers like medium and light turboprops, helicopters and certain UAVs, the tanker aircraft should be able to fly at low speeds. For that role medium/small size turboprop military transport aircraft, like the C295 from Airbus Military are ideally suited. This paper proposes a new palletized AAR kit for conversion of a transport A/C into a tanker. The kit includes all the needed air refueling systems, and can be installed on an existing military transport aircraft with rear cargo door ramp without big permanent modifications to the base platform.

We applied ultrasonic propagation imaging (UPI) system for rapid and reliable quality control of fuel tanks for a space launcher. The fuel tank is an aluminum-lined CFRP propellant tank. The UPI system uses Q-switched laser (QL) to generate ultrasonic wave on the test specimen, and laser mirror scanner (LMS) to control the laser impinging point that scans the area of interest with high speed. Each ultrasonic wave generated by laser impinging was received by a piezoelectric sensor with coordinate information of the scanned area. After ultrasonic propagation image processing, results with impact damage and manufacturing defect information of the fuel tank were presented.

Direct injection (DI) and jet ignition (JI), plus assisted turbocharging, have been demonstrated to deliver high efficiency, high power density positive ignition (PI) internal combustion engines (ICEs) with gasoline. Peak efficiency above 50% and power density of 340 kW/liter at the 15,000 rpm revolution limiter working overall λ=1.45 have been report-ed. Here we explore the further improvement in power density that may be obtained by replacing gasoline with ethanol or methanol, thanks to the higher octane number and the larger latent heat of vaporization, which translates in an increased resistance to knock, and permits to have larger compression ratios. Results of simulations are proposed for a numerical engine that uses rotary valves rather than poppet valves, while also using mechanical, rather than electric, assisted turbocharging. While with gasoline, the power density is 410-420 kW/liter, the use of oxygenates permits to achieve up to 475 kW/liter working with methanol.

An application of the new kind of the fuel for the diesel engine requires to conduct the qualification tests of the engines powered by this his fuel which allow assessing an impact of fuel on the engine reliability. Such a qualification test of the piston and turbine engines of the aircraft stationed on the ground and land vehicles is described in the NATO standardisation agreement (STANAG) 4195 as the AEP-5 test. The methodology and selected results of the qualification tests of the SW-680 turbocharged multi-purpose diesel engine fuelled with F-34 fuel have been presented in this paper. A dynamometric stand with the SW-680 engine has been described. Based on the preliminary results of the investigation it has been found that a change in a type of the fuel from IZ-40 diesel fuel into F-34 kerosene-type one has reduced a maximum engine torque by about 4%. This has been primarily due to a lower fuel density of F-34 by about 3%.

Cavitation erosion in aircraft engine and control systems is a major concern in hydrodynamic power units. In developing turbulent flow of low pressure and high velocities, a certain amount of cavitation erosion is not unusual. Cavitation can occur with the presence of fuel vapor or air bubbles dissolved in the fuel tank that are transported through the system. Cavitation erosion is caused by collapse of the bubble, which occurs violently and creates a pressure shock wave of fluid. Striking a solid surface, the shock wave can cause progressive damage if it persists. A kinetic cavitation power rate is developed to make a meaningful estimation of the cavitation erosion rate theoretically, which then can be validated with laboratory experiments. Theoretically, we manipulate parameters such as bubble size, collapse pressure, and energy for a given fuel system design, finding variation within each component of the system.

We have proposed the engine featuring a new compressive combustion principle based on pulsed supermulti-jets colliding through a focusing process in which the jets are injected from the chamber walls to the chamber center. This principle has the potential for achieving relatively silent high compression around the chamber center because autoignition occurs far from the chamber walls and also for stabilizing ignition due to this plug-less approach without heat loss on mechanical plugs including compulsory plasma ignition systems. Then, burned high temperature gas is encased by nearly complete air insulation, because the compressive flow shrinking in focusing process gets over expansion flow generated by combustion.

This specification covers the general requirements for the design, installation, and performance of thermal anti-icing equipment for the wings and empennage surfaces in aircraft.

This SAE Aerospace Information Report (AIR) identifies Propulsion EngineerÕs recommendations for the instrumentation that is required for the safe operation and maintenance of turbine engines as installed in helicopters. It should be used as a guide for cockpit layout, as well as a reference for maintenance considerations throughout the propulsion area. Propulsion instruments should receive attention early in the design phase of the helicopter. Maintenance and diagnostics recorders are not considered within the scope of this document. (See ARP1587, "Aircraft Gas Turbine Engine Monitoring System Guide".)