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Technical Paper

Zn-Ni Plating as a Cadmium Alternative

2007-09-17
2007-01-3837
In a 2-year program sponsored by SJAC, an aqueous electroplating process using alkaline Zn-Ni with trivalent chromium post treatment is under evaluation for high strength steel for aircraft application as an alternative to cadmium. Commercial Zn-15%Ni rack/barrel plating solutions are basis for plating aircraft parts or fasteners. Brightener was reduced from the original formula to form porous plating that enables bake-out of hydrogen to avoid hydrogen embrittlement condition. Properties of the deposit, such as appearance, adhesion, un-scribed corrosion resistance, and galvanic corrosion resistance in contact with Al alloy, were evaluated. Coefficient of friction was compared with Cd plating by torque-tension measurements. Evaluation of the plating for scribed corrosion resistance, primer adhesion, etc. will continue in FY2007.
Technical Paper

Zero-Waste PVD Cadmium for High Strength Steels

1998-11-11
983137
In spite of environmental issues related to cadmium and its electroplating process, electroplated cadmium is still extensively used in the aerospace and defense sectors. This trend is likely to continue especially for high strength steels because cadmium provides the best known corrosion and embrittlement protection for this application. Consequently, the environmental concerns related to the cadmium electroplating have been addressed using an alternative Zero-waste Physical Vapor Deposition (Z-PVD). This method does not use liquids, it recycles cadmium in situ, and is free of hydrogen embrittlement. The Z-PVD process is now in commercial production for the aerospace fasteners. The quality of the coatings has been at least equal to that of the electroplated cadmium.
Technical Paper

ZENITH: A Nano-Satellite for Atmospheric Monitoring

2015-09-15
2015-01-2395
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.
Standard

Water Solution Type Hand Fire Extinguisher

2014-11-25
CURRENT
AS245C
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

2015-09-15
2015-01-2563
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 Conditioning Assembly for Hermes ECLSS

1993-07-01
932072
This paper presents results of new development work carried out in the context of the Water Conditioning Assembly (WCA) which is part of the Liquid Management Section (LMS) of the Hermes Environmental Control and Life Support Subsystem (ECLSS) (see ref [1] and [2]). Its task is to condition and monitor the quality of highly pure water which has been produced in two fuel-cell stacks by the oxidation of hydrogen. This water will be used for different cooling elements (e.g. water evaporator, water sublimator) and as potable water for drinking and food purposes. The assembly consists mainly of: a hydrogen separator, providing for removal of dissolved and gaseous residual hydrogen from the fuel-cell water.
Technical Paper

Visual Investigation of Vapour-Gas Zone in Heat Pipe Condenser

1990-07-01
901274
The paper presents the results of the visual investigations of the working fluid vapour and non-condensible gaseous impurities interaction in low temperature heat pipe (LTHP) condensation zone. The effect of the transferred heat flow amount on the vapour and non-condensible gaseous impurity (NCG) separation is established. The obtained dependance allows to determine the minimal amount of the transferred heat flow from which the vapour and NCG will be dinamic mixed and the temperature profile will be simmetry in the heat pipe condensation zone. Water, ethanol, acetone, Freon-11 were used as the working fluid, while air, argon and helium as NCG.
Technical Paper

Vibratory Response of a Cylindrical Shell with Fixed Ends Subjected to a Unit Step Change of Pressure

1985-10-01
851984
The solution to the problem of establishing the value of the maximum stress in a uniform cylinder with fixed ends, subjected to a unit step change in pressure is presented. It is shown that the ratio of the maximum transient stress to the steady-state stress is a monotonically decreasing function of the damping ratio of the shell. The stress ratio approaches a value of 2 as the damping ratio and the parameter ψ, defined as
Technical Paper

Variable Compression Pistons

1990-08-01
901539
This paper traces the historical development of the BICERI variable compression ratio piston and its use in a number of engines. In early petrol experiments a variable compression piston covering the range from 6.5:1 to 16.5:1 showed significant efficiency improvements on 70 octane petrol. In the diesel engine field, Teledyne Continental increased the power of a V12 direct injection tank engine from 550 hp (30 hp per litre) to 1475hp (80 hp per litre) retaining the original crankcase and structure. At BICERI the output of a supercharged research engine was increased to 40 bar bmep with a peak cylinder pressure of only 165 bar. Military application lapsed with the preference for gas turbine engines, but the time is now right to explore the capabilities of variable compression within the wider automotive scene. Volkswagen have been working on a variable compression engine and have shown fuel consumption improvements up to 13% together with lower emissions.
Journal Article

Vapour Space Flammability Measurements of High Ethanol (“E85”) and Low Ethanol (“E10”) Winter Automotive Fuels: Effects of Fuel Composition and Vapour Pressure

2017-03-28
2017-01-1352
This paper presents an experimental study of the vapour space flammability of Fuel Ethanol (a high-ethanol fuel for Flexible Fuel Vehicles, commonly known as “E85”) and gasoline containing up to 10% ethanol (commonly known as “E10”). The seasonal minimum vapour pressure limits in specifications for automotive spark ignition fuels are intended, in part, to minimize the formation of flammable mixtures in the headspace of vehicle fuel tanks. This is particularly important at subzero temperatures, where the headspace mixture may not be rich enough to prevent combustion in the presence of an ignition source such as a faulty electrical fuel pump. In the current study, the upper temperature limits of flammability were measured for field samples of “E85” and “E10”, and a series of laboratory-prepared blends of denatured ethanol, Before Oxygenate Blending (BOB) gasoline, and n-butane.
Journal Article

Vapour Space Flammability Considerations for Gasoline Compression Ignition Vehicles Operating on “Dieseline” Blends.

2016-10-17
2016-01-2266
Gasoline Compression Ignition (GCI) has been identified as a technology which could give both high efficiency and relatively low engine-out emissions. The introduction of any new vehicle technology requires widespread availability of appropriate fuels. It would be ideal therefore if GCI vehicles were able to operate using the standard grade of gasoline that is available at the pump. However, in spite of recent progress, operation at idle and low loads still remains a formidable challenge, given the relatively low autoignition reactivity of conventional gasoline at these conditions. One conceivable solution would be to use both diesel and gasoline, either in separate tanks or blended as a single fuel (“dieseline”). However, with this latter option, a major concern for dieseline would be whether a flammable mixture could exist in the vapour space in the fuel tank.
Technical Paper

Validation Test of Advanced Technology for IPV Nickel-Hydrogen Flight Cells - Update

1992-08-03
929485
Individual pressure vessel (IPV) nickel-hydrogen technology was advanced at NASA Lewis and under Lewis contracts with the intention of improving cycle life and performance. One advancement was to use 26 percent potassium hydroxide (KOH) electrolyte to improve cycle life. Another advancement was to modify the state-of-the-art cell design to eliminate identified failure modes. The modified design is referred to as the advanced design. A breakthrough in the Low-Earth-Orbit (LEO) cycle life of IPV nickel-hydrogen cells has been previously reported. The cycle life of boiler plate cells containing 26 percent KOH electrolyte was about 40 000 LEO cycles compared to 3500 cycles for cells containing 31 percent KOH. The boiler plate test results are in the process of being validated using flight hardware and real time LEO test at the Naval Weapons Support Center (NWSC), Crane, Indiana under a NASA Lewis Contract. An advanced 125 Ah IPV nickel-hydrogen cell was designed.
Technical Paper

Utilization of Ethanol and Gas Oil Blended Fuels for Diesel Engine (Addition of Decanol and Isoamyl Ether)

1999-08-02
1999-01-2518
For a high speed Diesel engine , gas oil and lighter heavy oil are used in general, but, in order to reduce NOx (Nitorogine Oxide) in exhaust gas and also to prepare for the future world wide oil shortages, blends of alternative fuels, such as alcohols are of interest. These additive to Diesel engines have been studied for a long time in this institute, as well as in many other institutes in JAPAN. Here, the ignition temperature of blended gas oil and others, mixed with various alcohols (mainly ethanol) and Decanol or Isoamyl Ether, are measured independently to analyse the effect of this blending on the improvement of emission quality. Ethanol is of paticular interest because it is a fuel produced from all biomass including cereals, rice, corn, potatoes etc, crops widely produced in many places in the world, as seen in Figure 1.
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