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2015-09-27
Journal Article
2015-01-2662
Daniela Plachá, Pavlina Peikertova, Jana Kukutschova, Poh Wah Lee, Kristina Čabanová, Jiří Karas, Jana Kuchařová, Peter Filip
Abstract The brake wear contribution to the environmental pollution has been extensively discussed, with major focus on asbestos and heavy metals released to the environment. Only limited attention was paid to released organic compounds generated during friction processes, although the organic and carbonaceous components are not the minor part in brake lining formulations. Friction processes in brakes are associated with relatively high temperatures and high pressures on the friction surfaces which relates to the thermal decomposition of the organic components in friction materials and to brake lining thermal fade. Thus, this study focuses on the identification of organic compounds released from a model low metallic brake material.
2015-04-14
Journal Article
2015-01-0691
Salah H. R. Ali, Sarwat Z. A. Zahwi, Hassan H. Dadoura
Abstract The main aim of this work is to develop an identification method to demonstrate the crucial surfaces of automotive braking system. Two brand new brake discs manufactured by two different manufacturers are tested. A typical disc to the one of them was put under working condition in actual braking system. Dimensional and geometrical deviations are investigated using advanced engineering metrological technique. Mechanical properties, tribological characteristics and chemical analyses are investigated. A coordinate measuring machine, universal hardness tester, mass comparator and XRF spectrometer are used in these diagnoses. Measurements of dimensional and geometrical deviations such as disc thickness variations, thickness deviations, straightness, parallelism, runout of disc surfaces are conducted. A comparison between form deviations in disc surfaces have been carried out and analyzed.
2009-07-12
Journal Article
2009-01-2338
William Atwell, Paul Boeder, Richard Wilkins, Brad Gersey, Kristina Rojdev
Long-term exposure to the space radiation environment poses deleterious effects to both humans and space systems. The major sources of the radiation effects come from high energy galactic cosmic radiation and solar proton events. In this paper we investigate the radiation-mitigation properties of several shielding materials for possible use in spacecraft design, surface habitats, surface rovers, spacesuits, and temporary shelters. A discussion of the space radiation environment is presented in detail. Parametric radiation shielding analyses are presented using the NASA HZETRN 2005 code and are compared with ground-based experimental test results using the Loma Linda University Proton Therapy facility.
2009-07-12
Technical Paper
2009-01-2398
JMR Apollo Arquiza, Jean B. Hunter
Brine dewatering by evaporation on porous media, and collection of wastewater evaporation condensates rich in organic carbon, both provide favorable environments for microbial growth, such as mold overgrowth of rayon wicks in the AES brine evaporation system, and bacterial biofilms on condensate-wetted surfaces. The mold growth reported on AES wicks by Campbell et al. (2003) has been identified by microscopic and molecular techniques as chiefly Chaetomium spp, most likely C. globosum, with minor occurrence of Penicillium, and other fungal species. Bacteria from the genus Bacillus was also isolated. A stable bacterial consortium dominated by three species was recovered from initially-sterile glass surfaces wetted with sterile Biological Water Processor Effluent Ersatz (Verostko et al., 2004) and exposed to humidified air over a period of one week. The species were identified as Enterobacter aerogenes, Microbacterium foliorum and Pseudomonas putida by 16S rDNA sequencing.
2009-07-12
Journal Article
2009-01-2377
Ryan L. Kobrick, David M. Klaus, Kenneth W. Street
Operational issues encountered by Apollo astronauts relating to lunar dust were catalogued, including material abrasion that resulted in scratches and wear on spacesuit components, ultimately impacting visibility, joint mobility and pressure retention. Standard methods are being developed to measure abrasive wear on candidate construction materials to be used for spacesuits, spacecraft, and robotics. Calibration tests were conducted using a standard diamond stylus scratch tip on the common spacecraft structure aluminum, Al 6061-T6. Custom tips were fabricated from terrestrial counterparts of lunar minerals for scratching Al 6061-T6 and comparing to standard diamond scratches. Considerations are offered for how to apply standards when selecting materials and developing dust mitigation strategies for lunar architecture elements.
2009-07-12
Technical Paper
2009-01-2589
Sean Lillibridge, Ryan Stephan
Low Lunar Orbit (LLO) poses unique thermal challenges for the orbiting space craft, particularly regarding the performance of the radiators. The IR environment of the space craft varies drastically from the light side to the dark side of the moon. The result is a situation where a radiator sized for the maximal heat load in the most adverse situation is subject to freezing on the dark side of the orbit. One solution to this problem is to implement Phase Change Material (PCM) Heat Exchangers. PCM Heat Exchangers act as a “thermal capacitor,” storing thermal energy when there is too much being produced by the space craft to reject to space, and then feeding that energy back into the thermal loop when conditions are more favorable. Because they do not use an expendable resource, such as the feed water used by sublimators and evaporators, PCM Heat Exchangers are ideal for long duration LLO missions.
2009-07-12
Technical Paper
2009-01-2578
Gareth Toft, Tony Aitchison
Under contract to the UK Ministry of Defence (MoD), QinetiQ has been investigating the feasibility of an atmospheric carbon dioxide removal system, based on a novel hydrophobic adsorbent produced by impregnating mesoporous silica MCM41 with an imine. The silica/imine material has been found to perform better in humid conditions than when dry. This is in contrast to traditional zeolite molecular sieves, where carbon dioxide adsorption is adversely affected by the presence of water. The use of a hydrophobic adsorbent that functions regardless of the presence of water vapour, has the potential to greatly simplify temperature swing molecular adsorption systems by eliminating the need for an up-stream dryer bed, whilst eliminating the risk of the ammonia and monoethanolamine emissions associated with ‘wet amine’ scrubbers.
2009-07-12
Technical Paper
2009-01-2575
Emile Haddad, Roman V. Kruzelecky, Brian Wong, Wes Jamroz, Mohamed Soltani, Moushab Benkahoul, Mohamed Chaker, Philippe Poinas
MPB has developed advanced technologies based on smart radiator thin-film tiles (SRTs) employing V1−x−yMxNyOn, for the passive dynamic thermal control of space structures and payloads. The SRT has passed successfully the major ground tests and validated its performance for extended use in the harsh space environment, with a target of up to 15 years GEO, in preparation for a flight demonstration of this technology This paper describes the optimization of MPB's smart radiator and its validation of an efficient thermal control with the tuneability of thermo-optical properties. The thermal control of satellites is a critical subsystem that impacts on the performance and longevity of space payloads. MPB has developed advanced smart radiator devices (SRDs) for passive, dynamic thermal control of space structures and payload. The SRDs employ a nano-engineered, thin-film structure based on V1−x−yMxNyOn. Dopants, M and N, tailor the transition temperature of the IR emittance.
2009-07-12
Technical Paper
2009-01-2421
Michele Birmele, LaShelle McCoy, Monsi Roman, Michael S. Roberts
With the installation of the Water Recovery System (WRS) during mission STS-126 in 2008, the International Space Station (ISS) added the capability to recover clean water for reuse from crewmember urine and atmospheric humidity condensate, including EVA (Extravehicular Activity) wastes. The ability to collect, store and process these waste streams is required to increase potable water recovery and support the ISS crew augmentation planned for 2009. During ground testing of the Urine Processing Assembly (UPA), one of two primary component subsystems that comprise the WRS, significant fouling was repeatedly observed in stored urine pretreated with 0.56% of chromium trioxide and sulfuric acid. During initial observation, presumptive microbiological growth clogged and damaged flight-rated hardware under test as part of a risk-mitigation Flight Experiment (FE).
2009-07-12
Journal Article
2009-01-2444
David F Howard, Jay L. Perry, James C. Knox, Christian Junaedi
Developmental efforts are seeking to improve upon the efficiency and reliability of typical packed beds of sorbent pellets by using structured sorbents and alternative bed configurations. The benefits include increased structural stability gained by eliminating clay bound zeolite pellets that tend to fluidize and erode, and better thermal control during sorption leading to increased process efficiency. Test results that demonstrate such improvements are described and presented.
2009-07-12
Technical Paper
2009-01-2519
Leonid Vasiliev, Marco Marengo, Claudio Ferrandi, Stefano Zinna, Viktor Maziuk
An advanced method for LHP evaporator wick manufacturing is suggested. A small-scale loop heat pipe (LHP) with an innovative nickel wick has been fabricated and tested to examine its thermal performances. The LHP container and the tubing of the system are made of stainless steel and two liquids, namely hexane and acetone, have been used as LHP working fluids. The ‘low-cost’ characteristic is given by the reduction of operations which are needed for the LHP wick fabrication. In this study LHP wick was sintered directly inside of the stainless steel tube. Thus the fabrication costs of the LHP wick are less compared with the standard ones for two manufacturing processes: i) compressing the nickel powders and ii) inserting of the wick into the stainless steel tube after the sintering process. Since especially the second process is very delicate and associated to production failures, the present LHP is several times cheaper than the standard LHP.
2009-07-12
Technical Paper
2009-01-2536
Jared Ruckman, Edward Hodgson, Gregory Quinn
Mechanical counter-pressure (MCP) spacesuit designs have been a promising, but elusive alternative to historical and current gas pressurized spacesuit technology since the Apollo program. One of the important potential advantages of the approach is enhanced mobility as a result of reduced bulk and joint torques, but the literature provides essentially no quantitative joint torque data or quantitative analytical support. Decisions on the value of investment in MCP technology and on the direction of technology development are hampered by this lack of information since the perceived mobility advantages are an important factor. An experimental study of a simple mechanical counter-pressure suit (elbow) hinge joint has been performed to provide some test data and analytical background on this issue to support future evaluation of the technology potential and future development efforts.
2009-06-15
Journal Article
2009-01-1781
James McGeehan, Sheila Yeh, James Rutherford, Melvin Couch, Bengt Otterholm, Andreas Hinz, Andrew Walker
This paper reports on a field test with 23 Volvo D12C non-exhaust gas recirculation diesel engines using the Diesel Particulate Filter (DPF), Selective Catalytic Reduction (SCR), and urea system with Ultra-Low-Sulfur-Diesel (ULSD). This combination will be used to meet the on-highway emission standards for U.S. 2010, Japan 2010, and Europe 2013. Because of future widespread use of DPF-SCR, this study reports on our field experience with this system, and focuses on enhancing our understanding of the incombustible materials which are collected in the DPF with API CJ-4 and API CI-4 PLUS oils. The average weight of incombustibles was lower in the trucks using API CJ-4 oils at 1.0% sulfated ash, than in those using API CI-4 PLUS oils at 1.4% sulfated ash. The difference in weight between the two groups was highly significant. Further, the weight of the incombustibles per kilometer substantially decreased with each subsequent cleaning within a truck.
2009-05-19
Technical Paper
2009-01-2138
Jun Lu
The growing trend in demand for vehicles with diesel engines, especially in Europe, is a result of consumer demand for vehicles that offer greater fuel economy. This trend is gaining attention in North America as well. However, diesel vehicles are notorious for their NVH issues including engine vibrations that reverberate through the passenger cabin and noise that transmit through windshields as both structure-borne noise and airborne noise. Windshields, normally seen as the big hole in the front of the vehicle through which noise passes into the vehicle cabin, can be transformed to provide noise-mitigating properties by redesigning the PVB interlayer to reduce noise entering the vehicle. In essence, an acoustical windshield can help dissipate noises to a significant degree. NVH testing was performed on vehicles with diesel engines and acoustical-grade windshields, and vehicles with diesel engines and windshields made with standard PVB.
2009-04-20
Journal Article
2009-01-1390
Ronald J. Soldaat, Jamal Alghanem, Ming Chen, Stephen K. Kernosky, Thomas B. Stoughton, Lorraine Tervo
Over the past twelve years the Auto/Steel Partnership (A/SP) Tube Hydroforming Materials and Lubricants Team has been conducting projects to aid the implementation of tubular hydroforming in automotive applications. The approach taken has been to initially gain a basic understanding of the hydroforming process and potential issues and to then extend learning to real world applications of increasing complexity. The experimental project investigations have encompassed various steel grades with a recent focus on advanced high strength steel (AHSS) and tailor welded tubes (TWTs) in free expansion and corner fill processes using several types of lubricants. Project plans are developed based on identified knowledge gaps, barriers to implementation and technology needs as follows: Effects of forming operations prior to hydroforming including tube making, pre-bending and pre-forming. Forming limits (e.g. forming limit diagrams (FLDs)) and other failure criterion.
2009-04-20
Journal Article
2009-01-1393
K. Asim, W. F. Hosford, J. Pan, S.-T. Hong, K. S. Weil
Because niobium-clad 304L stainless steel sheets are considered for use as bipolar plates in polymer electrolyte membrane (PEM) fuel cells, their mechanical behavior and failure mechanism are important to be examined. As-rolled and annealed specimens were tested in tension, bending and flattening. The effects of annealing temperature and time on the mechanical behavior and failure mechanism were investigated. Micrographic analyses of bent and flattened specimens showed that the as-rolled specimens have limited ductility and that the annealed specimens can develop an intermetallic layer of thickness of a few microns. The annealed specimens failed due to the breakage of intermetallic layer causing localized necking and the subsequent failure of Nb layer. The springback angles of the as-rolled and annealed specimens were also obtained from guided-bend tests.
2009-04-20
Journal Article
2009-01-0993
Tadao Nishiyama, Osamu Murakami, Takashi Katsurai, Kazuhiko Adachi
The pressure of the combustion gas in a diesel engine is higher than that in a gasoline engine, so the cylinder head gasket that seals the combustion chamber is exposed to a severe environment. The sealability of the gaskets is affected not only by the gasket specifications, but also by the cylinder head, cylinder block, and the head bolts that clamp them. Consequently, in order to improve the performance of these gaskets, it is essential to enhance their material characteristics. Because the necessary characteristics of a gasket material are high strength and high fatigue strength, methods of realizing these enhancements were studied, and a new material was developed. It was confirmed that a gasket made using the newly developed material withstood high combustion pressure, and the gasket was used in a high performance diesel engine.
2009-04-20
Journal Article
2009-01-0277
Craig L. DiMaggio, Galen B. Fisher, Ken M. Rahmoeller, Mark Sellnau
Low-cost lean NOx aftertreatment is one of the main challenges facing high-efficiency gasoline and diesel engines operating with lean mixtures. While there are many candidate technologies, they all offer tradeoffs. We have investigated a multi-component Dual SCR aftertreatment system that is capable of obtaining NOx reduction efficiencies of greater than 90% under lean conditions, without the use of precious metals or urea injection into the exhaust. The Dual SCR approach here uses an Ag HC-SCR catalyst followed by an NH3-SCR catalyst. In bench reactor studies from 150 °C to 500 °C, we have found, for modest C/N ratios, that NOx reacts over the first catalyst to predominantly form nitrogen. In addition, it also forms ammonia in sufficient quantities to react on the second NH3-SCR catalyst to improve system performance. The operational window and the formation of NH3 are improved in the presence of small quantities of hydrogen (0.1–1.0%).
2008-11-11
Journal Article
2008-01-2930
T. J. Haugan, J. D. Long, L. A. Hampton, P. N. Barnes
The design of compact and lightweight power transmission devices was studied for specialized high power applications, including airborne with operating voltage fixed at 270 Volts and less than 30 meter length conductors. Only commercial-off-the-shelf components were considered for the design. It was found that by using superconducting wires operated at cryogenic temperatures instead of Cu conductors, a large increase of performance could be achieved; e.g. there is large reduction of heat loss; and for 5 MW-class or 20 kA power transmission there is a substantial reduction of weight of ∼ 80/kg per meter and an approximate 10x reduction of volume. A strong reduction of weight is achieved for > 1000 Amp power transmission.
2008-11-11
Technical Paper
2008-01-2893
Frank J. Puglia, Seth H. Cohen, Jeffrey C. Hall, Stuart G. Santee, R. Gitzendanner, Ratnakumar Bugga, Marshall C. Smart
Yardney Technical Product's (YTP) Lithion Division has developed advanced high power battery systems for numerous manned and unmanned systems. Specifically, for Unmanned Aerial Vehicles (UAVs), YTP has developed and delivered high energy designs for both the Global Hawk and the X-37. YTP has delivered high power batteries for electric torpedoes and high energy batteries for both the manned Advanced Seal Delivery System (ASDS) and unmanned underwater vehicles (UUVs). Additionally, YTP is underway in the Qualification testing of our fourth Unmanned Martian Vehicle (UMV), the Mars Science Laboratory (MSL). The performance and environmental requirements of these systems demonstrates the importance of battery thermal design and also some of the inherent limitations of the commercially available active materials. The above applications are largely military and aerospace, therefore a desire exists for the raw materials to come from conflict-secure sources.
2008-11-11
Journal Article
2008-01-2895
Za Johnson, Stephen Cordova, G. G. Amatucci
At present Li-ion batteries are the premier rechargeable energy storage technology and they offer a promising future as a power source for high energy density battery applications. Unfortunately, their high performance still falls short of energy density goals in many military ground battery and soldier portable applications. Although a number of factors within the battery cell contribute to this performance parameter, the most crucial one relates to how much energy can be stored in the positive and negative electrode materials of the lithium ion battery. Very little focus had been shown in the research of the electrochemistry of transition metal fluorides until Rutgers, The State University of New Jersey began its investigation. The reason for this apparent lack of interest in these compounds was that their intrinsic properties appeared to make them less desirable as possible electrode materials for lithium batteries.
2008-11-11
Technical Paper
2008-01-2852
David M. Shaddock, Aaron J. Knobloch, Shubhra Bansal, Chris Kapusta, Junghyun Cho, Harry Schoeller
This Department of Energy funded study represents the first significant investigation of polyimide flex as a substrate material for high temperature (>200°C) electronics packaging for downhole oil and gas exploration. This program examined at three key areas of package development: conductor adhesion to flex, through hole via reliability in flex, and high temperature interconnect methods for passive devices on flex. High temperature storage testing of different adhesion layers to flex was performed at 200 and 250°C in air and nitrogen for as long as 1000 hrs. Multiple adhesion materials and thicknesses were evaluated by measuring the peel strength of copper traces to polyimide. A Cr adhesion layer was selected due to its ability to maintain high peel strength during the high temperature storage testing. Thermal cycling of through hole vias between room temperature and 250°C for greater than 1200 cycles showed little degradation.
2008-10-06
Journal Article
2008-01-2395
Timothy Newcomb, Mark Sparrow, Brian Ciupak, Yousif Hadad, Jon Hassert
One of the most common failure modes for a friction interface is the accumulation of glaze on the friction material surface. Until recently, our analysis of glaze chemistry has always been consistent with the degradation of detergent, antiwear and extreme pressure additives in the oil. These additive degradation products are readily identified by the presence of Ca, P, S and Zn in an EDS analysis. In these cases the loss of friction performance, characterized by a gradual fade in friction coefficient and the concomitant development of a negative friction-speed gradient, is directly related to the loss of surface porosity due to the accumulation of glaze on the friction material surface. Over the past few years, the drive for better fuel economy in passenger cars has led to the introduction of lower viscosity oils possessing high viscosity index and shear stability. We have observed that these fluids also can lead to glaze accumulation on the friction surface.
2008-06-29
Journal Article
2008-01-2090
A. V. Shevade, M. A. Ryan, A. K. Kisor, K. S. Manatt, M. L. Homer, L. M. Lara
Polymers are one of the major constituents in electrical components. A study investigating pre-combustion off-gassing and particle release by polymeric materials over a range of temperatures can provide an understanding of thermal degradation prior to failure which may result in a fire hazard. In this work, we report simultaneous measurements of pre-combustion vapor and particle release by heated polymeric materials. The polymer materials considered for the current study are silicone and Kapton. The polymer samples were heated over the range 20 to 400°C. Response to vapor releases were recorded using the JPL Electronic Nose (ENose) and Industrial Scientific's ITX gas monitor configured to detect hydrogen chloride (HCl), carbon monoxide (CO) and hydrogen cyanide (HCN). Particle release was monitored using a TSI P-TRAK particle counter.
2008-06-29
Journal Article
2008-01-2119
Jose I. Rodriguez, Howard Tseng, Burt Zhang
The Moon Mineralogy Mapper (M3) instrument is one in a suite of twelve instruments which will fly onboard the Indian Chandrayaan-1 spacecraft scheduled for launch in 2008. Chandrayaan-1 is India's first mission to the Moon and is being managed by the Indian Space Research Organization (ISRO) in Bangalore, India. Chandrayaan-1 overall scientific objective is the photo-selenological and the chemical mapping of the Moon. The primary science objective of the M3 instrument is the characterization and mapping of the lunar surface composition in the context of its geologic evolution. Its primary exploration goal is to assess and map the Moon mineral resources at high spatial resolution to support future targeted missions. It is a “push-broom” near infrared (IR) imaging spectrometer with spectral coverage of 0.4 to 3.0 μm at 10 nm resolution with high signal to noise ratio, spatial and spectral uniformity.
2008-06-29
Journal Article
2008-01-2163
Lawrence W. Townsend, David Yancey, Peter Thomas, William Atwell
Estimates of the effectiveness of the high-hydrogen containing materials, sodium alanate and ammonia borane, are made by calculating dose and dose equivalent for the 1977 solar minimum and 1970 solar maximum galactic cosmic ray spectra and for the large solar particle event spectra from the space era event of August 1972 and comparing their shielding effectiveness with that of polyethylene.
2008-06-29
Technical Paper
2008-01-2037
Jose I. Rodriguez, Howard Tseng, Burt Zhang, Arthur Na-Nakornpanom, Robert S. Leland
The Moon Mineralogy Mapper (M3) instrument is scheduled for launch in 2008 onboard the Indian Chandrayaan-1 spacecraft. The mission is managed by the Indian Space Research Organization (ISRO) in Bangalore, India and is India's first flight to the Moon. M3 is being developed for NASA by the Jet Propulsion Laboratory under the Discovery Program Office managed by Marshall Space Flight Center. M3 is a state-of-the-art instrument designed to fulfill science and exploratory objectives. Its primary science objective is to characterize and map the lunar surface composition to better understand its geologic evolution. M3's primary exploration goal is to assess and map the Moon mineral resources at high spatial resolution to support future targeted missions. M3 is a cryogenic near infrared imaging spectrometer with spectral coverage of 0.4 to 3.0 μm at 10 nm resolution with high signal to noise ratio, spatial and spectral uniformity.
2008-06-29
Journal Article
2008-01-2044
M. A. Ryan, A. V. Shevade, A. K. Kisor, K. S. Manatt, M. L. Homer, L. M. Lara, H. Zhou
The Third Generation ENose is an air quality monitor designed to operate in the environment of the US Lab on the International Space Station. It detects a selected group of analytes at target concentrations in the ppm regime at an environmental temperature range of 18 - 30 °C, relative humidity from 25 - 75% and pressure from 530 to 760 torr. The abilities of the device to detect ten analytes, to reject confounders as “unknown” and to deconvolute mixtures of two analytes under varying environmental conditions has been tested extensively in the laboratory. Results of ground testing showed an overall success rate for detection, identification and quantification of analytes of 87% under nominal temperature and humidity conditions and 83% over all conditions.
2008-06-23
Technical Paper
2008-01-1734
Zhao Hongwei, Chen Xiaokai, Lin Yi
This presentation evaluates the contribution of multi-objective programming scheme for the conceptual design of the Hybrid Electric Vehicle frame's structure using topological optimization. The compromise programming method was applied to describe the statically loaded multicompliance topology optimization. Solid Isotropic Material with Penalization (SIMP) was used as the interpolation scheme to indicate the dependence of material modulus upon regularized element densities. The sequential convex programming approach was applied to solve the optimization problem. The application on the chassis frame was used to demonstrate the characteristics of the presented methodologies based on the commercial software package OptiStruct.
2008-06-23
Technical Paper
2008-01-1775
Jun Zhu, Tianyou Guo, Yukun Shi, Jin Cao, Wenhui Zhang
The price of fossil fuels and the increasing inexorable energy crisis have become vital issues for everyone. Tongji University EconoPower Racing Team was established to participate in the “Honda EconoPower Cup” annually. Every contestant in the competition must finish a certain distance in the fixed time, with the gasoline supplied by the committee. After that the committee will measure the fuel consumption of every team and calculate the distance per liter fuel (the farther the better) to determine the champion. In order to enhance the EP vehicle's achievement we've made some improvements, such as framework, body, engine's optimization and so on. In this passage we mainly state some details of our research approaches in framework, steering, transmission, shape and driving strategy. The main technologies were: friction reduction, lightweight, enhancement of power train efficiency, tire selection and driving strategy.
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