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Technical Paper

“Fuel Flow Method2” for Estimating Aircraft Emissions

In recent years there has been increasing interest in quantifying the emissions from aircraft in order to generate inventories of emissions for climate models, technology and scenario studies, and inventories of emissions for airline fleets typically presented in environmental reports. The preferred method for calculating aircraft engine emissions of NOx, HC, and CO is the proprietary “P3T3” method. This method relies on proprietary airplane and engine performance models along with proprietary engine emissions characterizations. In response and in order to provide a transparent method for calculating aircraft engine emissions non proprietary fuel flow based methods 1,2,3 have been developed. This paper presents derivation, updates, and clarifications of the fuel flow method methodology known as “Fuel Flow Method 2”.
Technical Paper

‘Issues and Behaviors of Airborne Particulate Matters under Microgravity Environment’

During several ISS missions, there were false alarms at both US and Russian smoke detectors. High local airborne particulate concentrations and interior deposits are considered the causes for such anomalies. Alternatives are proposed to replace or complement these faulty smoke detectors. The entrained zeolite particles may play a role in causing problems with check valves and air save pumps in CDRA and Vozdukh. Another incidence has been the dispersion of particulates out of Metox regeneration oven. Particulate matters with aerodynamic diameter of 15 microns and above, which normally settle down on earth, stay airborne under micro-gravity and thereby cause the above-mentioned nuisances. The motion of such a particle along a gas stream with an initial velocity can be expressed by theoretical equations. Stokes' Law leads to the descriptions of inertial precipitation of aerosols that are important in solving the issues.
Technical Paper

srv-k Status Aboard the International Space Station During Missions 15 and 16

The paper summarizes the experience gained on the ISS water management system during the missions of ISS-1 through ISS-16 (since November 2 2000, through December 31, 2007). The water supply sources and structure, consumption and supply balance at various phases of space station operation are reviewed. The performance data of the system for water recovery from humidity condensate SRV-K and urine feed and pretreatment system SPK-U in the Russian orbital segment are presented. The key role of water recovery on a board the ISS and the need to supplement the station's water supply hardware with a system for water reclamation from urine, water from a carbon dioxide reduction system and hygiene water is shown.
Technical Paper

Zirconia Electrolysis Cells for Oxygen Generation from Carbon Dioxide for Mars In-Situ Resource Utilization Applications

A zirconia electroysis cell is an all-solid state (mainly ceramic) device consisting of two electrodes separated by a dense zirconia electrolyte. The cell electrochemically reduces carbon dioxide to oxygen and carbon monoxide at elevated temperatures (800 to 1000°C). The zirconia electrolysis cell provides a simple, lightweight, low-volume system for Mars In-Situ Resource Utilization (ISRU) applications. This paper describes the fabrication process and discusses the electrochemical performance and other properties of zirconia electrolysis cells made by the tape calendering method. Electrolytes produced by this method are very thin (micrometer-thick); the thin electrolyte reduces ohmic losses in the cell, permitting efficient operation at temperatures of 800°C or below.
Technical Paper

ZENITH: A Nano-Satellite for Atmospheric Monitoring

This paper describes the ZENITH Nano-Satellite cum planetary atmospheric entry vehicle, called CanSat, the first Nano-Satellite project that has been developed by Delhi Technological University (Formerly Delhi College of Engineering), India. The satellite will function for monitoring the concentrations of various gases in the atmosphere. For this, the satellite consists of arduino microcontroller interfaced with the various Micro-electromechanical system (MEMS) gas sensors for measuring the concentrations of various gases such as carbon dioxide, carbon monoxide, methane, nitrous oxides, ozone, etc. The data obtained from the CanSat will be transmitted to the ground station where all the data will be stored and also the locations will be stored using GPS sensor. The academic goal of this project is to recruit students to the field of space science and technology.
Technical Paper

X-Rays and Gamma Rays-Their Industrial Application

THE X-ray spectrum readily adapts itself to problems in chemical analysis and crystal formation. It is effective on very minute particles which otherwise cannot be segregated. A permanent record is made, and the specimens may be used over and over again, as the X-ray is non-destructive. As a means of inspection, X-ray clearly shows the interior of objects such as weldings castings, forgings, cold-worked metals, and so on. Inhomogeneities that are very slight in width and a fraction of one per cent in thickness are seen easily on a radiograph. Defects thus found may be eliminated summarily by checking various steps in production.
Technical Paper

X-Ray - A Necessary Tool for Detecting Incipient Structural Failures in Service Aircraft

X-ray is an indispensable aid in locating and determining the extent of incipient failures in structure which is inaccessible by position or covered by multiple layers of metal. It is also the most feasible method for checking oil coolers for contamination; bonded honeycomb panels for water; fuel lines for erosion; and with a 360 deg emission tube, fuselage frames for structural integrity without removing the interior upholstery and panels from the passenger compartment or cargo compartments.
Technical Paper

Worst Case Solar Energetic Particle Events for Deep Space Missions

Over the past two decades, various models of “worst case” solar energetic particle event (SPE) spectra have been proposed in order to place an upper bound on the likely doses to critical body organs of astronauts on missions outside Earth’s geomagnetic field. In this work, direct comparisons of organ dose estimates for various models of “worst case” SPE spectra are made by using the same transport code (BRYNTRN) and the same human geometry model (Computerized Anatomical Man). The calculations are made assuming nominal thicknesses of spacecraft aluminum shielding. Discussions of possible acute exposure responses from these exposures are presented.
Technical Paper

Wind Tunnel Measurements of Simulated Glaciated Cloud Conditions to Evaluate Newly Developed 2D Imaging Probes

Instrumentation that has been used for characterization of mixed-phase and glaciated conditions in the past, like the OAP probes, are subject to errors caused by variations in diffraction on the images away from the object plane and by the discrete nature of their particle detection and sizing. Correction methods are necessary to consider their measurements adequate for high ice water content (IWC) environments judged to represent a significant safety hazard to propellers and turbofan engine operability and performance. For this reason, within the frame of EU FP7 HAIC project, instrumentation characterization and validation is considered a major element need for successful execution of flight tests campaigns. Clearly, instrumentation must be sufficiently reliable to assess the reproducibility of artificial clouds with high ice water content generated in icing tunnels.
Technical Paper

Wet-Oxidation Waste Management System for CELSS

A wet oxidation system will be useful in CELSS as a facility to treat organic wastes and to redistribute inorganic compounds and elements. However at rather higher temperatures needed in this reaction, for instance, at 260 °C, only 80% of organic carbon in a raw material can be oxidized, and 20% of it will remain in the liquid mainly as acetic acid, which is virtually non-combustible. Furthermore, nitrogen is transformed to ammonium ions which normally cannot be absorbed by plants. To resolve these problems, it becomes necessary to use catalysts. Noble metals such 33 Ru, Rh and so on have proved to be partially effective as these catalysts. That is, oxidation does not occur completely, and the unexpected denitrification, instead of the expected nitrification, occurs. So, it is essential to develop the catalysts which are able to realize the complete oxidation and the nitrification.
Technical Paper

Wet Oxidation of a Spacecraft Model Waste

Wet oxidation was used to oxidize a spacecraft model waste under different oxidation conditions. The variables studied were pressure, temperature, duration of oxidation, and the use of one homogeneous and three heterogeneous catalysts. Emphasis is placed on the final oxidation state of carbon and nitrogen since these are the two major components of the spacecraft model waste and two important plant nutrients.
Technical Paper

Welding With a High-Power CO2 Laser

The application of a production-oriented high-power CO2 laser system for the welding of auto underbody components is reported. Sheet metal sections, varying in thickness from 0.060-0.135 in, are welded at speeds up to 500 in/min at 6 kW. An overview of recent developments in laser welding is presented along with a discussion of the laser deep-penetration weld phenomenon. A comparison is made between laser and electron-beam welding performance.

Weber Metals unveils new 540-meganewton press for aerospace components

Weber Metals Inc., a division of Otto Fuchs KG of Germany, unveiled a new, $180 million, 60,000-ton press at its 2.5-acre facility in Paramount, California, southeast of Los Angeles. It sets a record as the highest tonnage hydraulic forging press in the Americas and the largest privately funded forging press investment in the world.
Technical Paper

Wear of Tire Tread/Carcass Composites

A multi-axial dynamic test instrument was designed to perform wear testing of actual aircraft tires as well as tread/carcass composite specimens under laboratory loading conditions which simulate the elements of take-off, landing and taxiing operations. The wear tester consists of a self-spinning abrading head, mounted on the actuator of a servo-hydraulic test system, which faces either (1) the tread surface of a composite specimen clamped by a horizontal stretch frame or (2) the tread region of actual inflated tires. The test concept has been partially proven in the case of tread/carcass composite specimens by building a proto-type test apparatus and operating it successfully. In the current test set-up, the specimen is subjected to static tension to simulate a circumferential load in the tire footprint and the tread surface is in periodic contact with an abrading head under a specific level of pressure.
Technical Paper

Water Vapor Pollution of the Upper Atmosphere by Aircraft

The two combustion products which future technology will be unable to eliminate from present day jet engines are carbon dioxide and water vapor. The potential climatic change effects of carbon dioxide are considered to be a small part of a larger CO2 problem. Water vapor added to the troposphere forms contrails. The paper will assess the non-conclusive evidence of increased cirrus cloudiness at certain locations. Finally the potential climatic effects of added water vapor in the stratosphere on the radiation budget, the small decrease in ozone, and polar night cloudiness is evaluated in the light of future commercial aviation injections of water vapor.

Water Solution Type Hand Fire Extinguisher

This specification covers the following types and classes of extinguishers: Type I Stored pressure type Category A - Operational Temperature range −40 to +140 °F (−40 to +60 °C) Category B - Operational Temperature range +35 to +140 °F (+1.7 to +60 °C) Type II Cartridge operated type Category A - Operational Temperature range −40 to +140 °F (−40 to +60 °C) Category B - Operational Temperature range +35 to +140 °F (+1.7 to +60 °C)
Technical Paper

Water Solubility in Different Alternative Jet Fuels: A Comparison with Petroleum-Based Jet Fuel

The paper presents an extensive assessment of the hygroscopic characteristics of a number of alternative jet fuel blends. These are blended with conventional Jet A-1 to conform with current aviation standards at a 50:50 ratio by volume, except for DSHC (Direct Sugar to Hydrocarbon), which is blended at 10% DSHC and 90% Jet A-1. Given the lack of information available on the water solubility of alternative jet fuels, an effective analysis of experimental data about this characteristic in six different alternatives was performed. These included four ASTM approved alternatives (two Fischer-Tropsch (FT) synthetics from coal and natural gas, one HEFA (Hydroprocessed Esters and Fatty Acids) derived from camelina and DSHC. An extra two alternatives currently under consideration for ASTM approval were also tested; ReadiJet and an ATJ (Alcohol to Jet).
Technical Paper

Water Reclamation Using Spray Drying

Spray drying is a continuous physical separation process where a solution is sprayed into a hot drying medium. The resulting products are dry solute particles and the drying medium bearing the solvent vapor. Using one of several methods the solvent is recovered from the drying medium. The exact nature of the dried solid and recovered solvent depends on the physical and chemical properties of the feed and the design and operation of the dryer. In this paper we discuss progress made on the development of a prototype for advanced life support applications, and provide data on its purification abilities. A system processing 1 kg hr−1 of aqueous brine solution consumes on the order of 1000 W, but this value was strongly tied to other processing parameters such as dryer inlet and exit temperatures and the heating mode. Analysis of recovered water having an initial concentration of 48000 ppm TDS had between 12 and 134 ppm TDS and strongly depended on the processing conditions.
Technical Paper

Water Injection: Disruptive Technology1 to Reduce Airplane Emissions and Maintenance Costs

Water injection is an old aviation technology that was previously used to generate increased engine power during takeoff. If water injection were now to be used without increasing thrust, it could result in large reductions in takeoff NOx emissions and would most likely enable longer engine life and reduced operator costs. Due to the cooling action of evaporating water, a large temperature reduction will be experienced at the point where the water is injected into the engine. This could improve combustion emissions, such as temperature-sensitive NOx, and help reduce temperatures throughout the turbine section of the engine. The two current preferred methods of water injection are: (1) direct injection into the combustor, and (2) misting of the conditioned water before the engine's compressor. Combustor injection could achieve up to 90% NOx reduction and offer few implementation challenges as it has been used in aero-derivative industrial engines for over 30 years.