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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.

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.

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 is reissued for application to helicopters.

In recent years, interest has been growing in the 2-Stroke Diesel cycle, coupled to high speed engines. One of the most promising applications is on light aircraft piston engines, typically designed to provide a top brake power of 100-200 HP with a relatively low weight. The main advantage yielded by the 2-Stroke cycle is the possibility to achieve high power density at low crankshaft speed, allowing the propeller to be directly coupled to the engine, without a reduction drive. Furthermore, Diesel combustion is a good match for supercharging and it is expected to provide a superior fuel efficiency, in comparison to S.I. engines. However, the coupling of 2-Stroke cycle and Diesel combustion on small bore, high speed engines is quite complex, requiring a suitable support from CFD simulation.

In the 1980's, USBI introduced automated waterjet coatings removal into NASA's Space Shuttle program by activating robot cells to remove thermal protection coatings from solid rocket booster components. In the 1990's, USBI has applied this technology to coatings removal from jet engine components. Using this environmentally compatible, pollution prevention technology USBI has demonstrated the removal of ceramic coatings from vanes; magnesium zirconate coatings from combustion chambers and burner cans; plasma coatings from stator rings, knife edge seals, and Up segments; plasma and rubber coatings from high pressure compressor cases; hardface coatings from inner vane supports; tin bismuth shuttles removed from blades; boron nitrite coatings from forged disks; and aluminum oxide coatings from blades.

This paper deals with a thrust generation method which can be applied to nuclear as well as chemical propulsion systems. It takes into consideration both incompressible and compress-ible flow cases, however both of these cases are based on one dimensional flow within an ideal rocket framework. In the case of constant area duct steady state flow the obtained Induced Thrust (IT) formula is: where p1 and p2 are opposing pressure fields and u* is a function of u2, p2 and u1 (u1 and u2 being opposing gas efflux velocities). For the compressible and incompressible flow fields, IT formulas are obtained but they are not as reliable. One feasible application for this launch-propulsion method is the Joined-Ship model. In this model the combustion chamber pressure within one space vehicle acts as the back pressure of the joined space vehicle and vice-versa.

The results of computational investigations carried out to clarify the possibilities of hydrogen scramjet thrust uprating in hypersonic flight (M >8) by adding to the fuel substances with higher density are presented. Thrust, specific impulse and density impulse are calculated while adding nitrogen, oxygen, water or inert liquated gases. Fuel is injected tangentially to air flow into combustion chamber with high velocity through gas generator nozzles. For scramjet boosting in hypersonic flight it is suggested to add oxygen to stoichiometric part of hydrogen instead of excessive part of hydrogen.

This SAE Aerospace Information Report (AIR) presents information on gas energy limited propulsion engine starting systems employed in commercial and military applications and remote industrial sites. The types of systems discussed utilize solid propellant cartridge gas, monopropellant hydrazine gas, bipropellant gas, compressed stored gas, and cryogenic stored nitrogen. Presented information conveys design features, performance capabilities and system limitations with methods of computing results.

This SAE Aerospace Information Report (AIR) is a review of the general characteristics of power sources that may be used to provide secondary, auxiliary, or emergency power for use in aircraft, space vehicles, missiles, remotely piloted vehicles, air cushion vehicles, surface effect ships, or other vehicles in which aerospace technology is used. The information contained herein is intended for use in the selection of the power source most appropriate to the needs of a particular vehicle or system. The information may also be used in the preparation of a power source specification. Considerations for use in making a trade study and an evaluation of the several power sources are included. More detailed information relating to specific power sources is available in other SAE Aerospace Information Reports or in Aerospace Recommended Practices.

This SAE Aerospace Information Report (AIR) is a review of the general characteristics of power sources that may be used to provide secondary, auxiliary, or emergency power for use in aircraft, space vehicles, missiles, remotely piloted vehicles, air cushion vehicles, surface effect ships, or other vehicles in which aerospace technology is used. The information contained herein is intended for use in the selection of the power source most appropriate to the needs of a particular vehicle or system. The information may also be used in the preparation of a power source specification. Considerations for use in making a trade study and an evaluation of the several power sources are included. More detailed information relating to specific power sources is available in other SAE Aerospace Information Reports or in Aerospace Recommended Practices.

This SAE Aerospace Information Report (AIR) is a review of the general characteristics of power sources that may be used to provide secondary, auxiliary, or emergency power for use in aircraft, space vehicles, missiles, remotely piloted vehicles, air cushion vehicles, surface effect ships, or other vehicles in which aerospace technology is used. The information contained herein is intended for use in the selection of the power source most appropriate to the needs of a particular vehicle or system. The information may also be used in the preparation of a power source specification. Considerations for use in making a trade study and an evaluation of the several power sources are included. More detailed information relating to specific power sources is available in other SAE Aerospace Information Reports or in Aerospace Recommended Practices.