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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.

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.

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%.

Butanol, a four-carbon alcohol, is considered in the last years as an interesting alternative fuel, both for Diesel and for gasoline application. Its advantages for engine operation are: good miscibility with gasoline and diesel fuels, higher calorific value than ethanol, lower hygroscopicity, lower corrosivity and possibility of replacing aviation fuels. Like ethanol, butanol can be produced as a biomass-based renewable fuel or from fossil sources. In the research project, DiBut (Diesel and butanol) addition of butanol to Diesel fuel was investigated from the points of view of engine combustion and of influences on exhaust aftertreatment systems and emissions. One investigated engine (E1) was with emission class “EU Stage 3A” for construction machines, another one, engine (E2) was HD Euro VI. The most important findings are: with higher butanol content, there is a lower heat value of the fuel and there is lower torque at full load.

This information report presents a preliminary discussion of liquid propellant gas generation (LPGG) systems. A LPGG system, as used herein, is defined as a system which stores a liquid propellant and, on command, discharges and converts the liquid propellant to a gas. The LPGG system can interface with a gas-to-mechanical energy conversion device to make up an auxiliary power system. Figure 1 shows a block diagram of LPGG system components which include a propellant tank, propellant expulsion system, propellant control and a decomposition (or combustion) chamber. The purpose of this report is to provide general information on the variety of components and system arrangements which can be considered in LPGG design, summarize advantages and disadvantages of various approaches and provide basic sizing methods suitable for initial tradeoff purposes.

This information report presents a preliminary discussion of liquid propellant gas generation (LPGG) systems. A LPGG system, as used herein, is defined as a system which stores a liquid propellant and, on command, discharges and converts the liquid propellant to a gas. The LPGG system can interface with a gas-to-mechanical energy conversion device to make up an auxiliary power system. Figure 1 shows a block diagram of LPGG system components which include a propellant tank, propellant expulsion system, propellant control and a decomposition (or combustion) chamber. The purpose of this report is to provide general information on the variety of components and system arrangements which can be considered in LPGG design, summarize advantages and disadvantages of various approaches and provide basic sizing methods suitable for initial tradeoff purposes.

This recommended practice is written to cover the installation of combustion heaters used in the following applications.

This aerospace recommended practice covers requirements for a self-propelled, boom type aerial device, equipped with an aircraft deicing fluid spraying system. The unit shall be highly maneuverable for deicing all exterior surfaces of intermediate size aircraft, e.g. DC-9, B-727 and B-737. The vehicle will also be used for aircraft maintenance and inspection. The vehicle shall be suitable for day and night operations.

Parameters to consider and various methods of measuring spark energy of aviation ignition systems.

These standards are written to cover internal combustion heat exchanger type heaters used in the following applications:

The Aircraft Engine Starting and Auxiliary Power System Glossary presents definitions of terms commonly encountered and associated with aircraft engine starting and auxiliary power systems. Terms have been arranged alphabetically.

This document describes a number of jet fuel properties and where applicable gives the specification limits for Jet A and Jet A-1, though the properties are generally applicable to all turbine fuels. Later versions of this document will give more details on specification limits for other similar fuels, such as TS-1, where they differ from Jet A and Jet-A1. It gives details about the possible impact on airframe fuel system design.

This specification covers mixtures of methyl alcohol or ethyl alcohol, or both, with water in the form of liquids.

This specification covers mixtures of methyl alcohol and/or ethyl alcohol, with water in the form of liquids.

This specification covers mixtures of methyl alcohol and/or ethyl alcohol with water in the form of liquids.

This document is reissued for application to helicopters.