Army Materiel Command Research Articles

Increasing Army Supply Chain Performance Using an Integrated End-to-End Metrics System

Army Materiel Command and the University of Alabama in Huntsville partnered to develop an integrated end-to-end performance metrics system. The integration includes data pulls from multiple data systems into a metrics calculation and aggregation system that generates strategic performance metrics such as Customer Wait Time (CWT), with capabilities spanning from bottom-up supply chain performance aggregation capabilities to in-depth traceability to source (tactical) level data and documents. To support the best national defense, we must ensure that our warfighters receive the supply support they need in a timely and efficient manner. Supporting this effort requires a near-real-time system that measures and reports on supply chain strategic performance characteristics such as CWT. Data integrity is an integral part of the process, as is reaching common agreement on appropriate data sources, algorithms to calculate metrics, and the design of a visual dashboard that supports leadership decisions and performance evaluation, with drill-down capability for lower level decision making.

(Invited) Development of Alkaline- and Bipolar-Membranes for Hybrid Fuel Cell Applications

The development of technologies which offer efficient and scalable energy conversion and storage is a challenge of considerable importance. Potential applications range from the integration of renewable energy supplies into the domestic power grid to reducing the logistic burden of supplying energy to our military and defense forces. Electrochemical processes are a natural fit for addressing many of these problems; however, system limitations and technical issues confound development efforts. Cost, reliability, scalability, and ease of integration are often among the leading challenges for established domestic technologies, whereas size, weight, storage/transportability, and environmental considerations are of utmost importance for defense applications. Research and development efforts for electrochemical energy conversion and storage technologies are driven by materials requirements. Materials in these electrochemical systems typically have demanding functional requirements (e.g., conductivity, catalyst activity, selectivity, mechanical strength, etc.), which must be met under aggressive operating conditions (e.g., acidic or basic electrolytes, the presence of strong solvents and/or contaminants, highly oxidizing and reducing electrode processes, high temperatures, etc.). All of these functional requirements must be met with expectations for little-to-no degradation during operation and cycling (e.g., loss in active catalyst area, poisoning or chemical degradation, corrosion, fatigue, crack formation, etc.). In many cases the individual constituent materials cannot meet the complex and intertwined functional, environmental, and stability requirements alone, which has driven research and development efforts towards the use of heterogeneous materials. Our own research and development efforts focus on hybrid acidic- and alkaline-membranes for portable fuel cell applications [1-2]. Proton exchange membrane (PEM) electrolytes are relatively well established. Alkaline anion exchange membrane (AEM) electrolytes have more recently come to prevalence. AEMs have been ushered into the fuel cell community based on the prospect of developing cheaper and more compact systems via reductions in noble-metal catalyst content, membrane and packaging materials costs, and water and fuel management requirements [3]. However, development efforts have been hindered by challenges with materials performance and stability [3-5], penalties for anodic processes including hydrogen oxidation [6], and thermodynamic and resistive losses associated with the presence of carbon dioxide [7-8], among others. These challenges have led us to explore the development of hybrid-membrane approaches, such as the bipolar membrane which was shown by Unlu et al [9]. We believe that this type of approach can mitigate some of the catalyst and water/fuel management challenges. However, a suitable AEM and acid-alkaline membrane interface are needed for such an approach. This has led us to study the modification of the underlying AEM materials as well as the introduction of heterogeneity through processing (e.g., via electrospinning processes popularized for fuel cells in the PEM community [10]). In this modeling and theory focused talk, we address the introduction of heterogeneity into membrane electrolyte materials, its influence on key material properties, and the corresponding impact of its integration to bipolar membrane fuel cells. Acknowledgement: The authors gratefully acknowledge the support of the U.S. Department of the Army, Army Materiel Command, and U.S. Army Research Development and Engineering Command.

A Multiscale Approach Toward the Design and Understanding of Stable and Conductive Anion Exchange Membrane Materials

Improved anion exchange membrane (AEM) materials are needed to develop next generation electrochemical devices including fuel cells. In recent years, largely spurred by some developments with radiation grafted AEM materials out of the laboratories of Robert Slade and John Varcoe, there has been significant attention from within the energy conversion/storage communities [1-3]. In additional to the interest in the use of AEM materials for fuel cells [1-3], the community has given additional consideration to their use for areas including chemical processing and energy storage [3-6], electrolysis and solar-to-fuel production [3,6], desalination and dialysis [3], and purification and separation processes [3]. Many of the interest in these materials is a result of the opportunities that may be presented by a stable, anion-conducting polymer electrolyte materials. In this talk we will highlight our collaborative, simulation-focused efforts to develop and understand high performance AEM materials for electrochemical applications. Among other things, we will discuss our efforts to develop, validate, and apply simulation methodologies that can provide new and fundamental insights into the nature of the membrane(s) cationic stability, anionic conductivity, and the uncertainty in our respective models that range from atomistic to continuum scales. These multiscale modeling approaches include everything from atomistic MD simulations using reactive (ReaxFF) and polarizable force fields, to coarse-grained molecular dynamics simulations with developed using uncertainty quantification (UQ) based methodologies and continuum level modeling approaches. For our initial efforts that we will discuss in this talk, we utilize relatively simple backbone materials such as Poly(2,6-dimethyl-1,4-phenylene oxide) (PPO). These backbone materials are effectively used as a model material system. This enables us to develop and validate simulation methods that can predict and resolve the proper structure-property relationships; a key step before moving to more complex materials. Further, the simpler PPO-type backbone materials provide a key advantage at this stage in that they can concurrently be (i) processed, synthesized, and characterized in our labs, and (ii) subjected to unique processing methods/conditions that includes both casting and electro-spinning processes. This last capability is salient because the focus of the model and simulation development efforts are on the application to multi-scale systems. The ability to concurrently process the materials using different methods (i.e., cast, electro-spun, and co-spun with an inert matrix material) and under different conditions can drastically influence the material’s morphologies, structures, ordering, and properties. Acknowledgments: KNG, JPM, and DC gratefully acknowledge the support of the U.S. Department of the Army, Army Materiel Command, and U.S. Army Research Development and Engineering Command. This work was completed, in part, through the U.S. Army Research Laboratory’s Enterprise for the Multiscale Research of Materials (EMRM). This work was completed in conjunction with an Army Research Laboratory EMRM’s Multiscale Modeling of Electronic Materials (MSME) Collaborative Research Alliance (CRA). VM, LCJ, JL, DB, JBH, ZL, AvD, WZ, and RMK gratefully acknowledge the financial support of the MSME CRA.

Understanding the Acid-Alkaline Bipolar Membrane Electrolyte for Fuel Cell Applications

One of the challenges confronting fuel cell technologies is their integration into a practical, robust system. The Balance of Plant (BoP) components needed to manage the fuel and oxidant, humidification and/or water removal, and thermal loads are often cumbersome to integrate. These issues can present unique requirements and are persistent across most types of fuel cell applications (e.g., wearable and portable, transportation, backup and primary power, etc.) and fuel cell types (e.g., polymer electrolyte, direct methanol, reformed methanol, solid oxide, and so forth). The research and development efforts presented in this work are specifically geared toward wearable and portable power applications. In this configuration, a compact, lightweight, and cost effective system with a high specific energy (density) is desired. Polymer electrolyte fuel cells with energy dense liquid fuels such as methanol are often used in attempt to fill this need. Direct methanol fuel cell (DMFC) systems have shown that they can reliably provide large energy density values over a wide range of environmental and operational conditions; however, DMFCs size/footprint and cost continue to be a drawback. The size and complexity of present DMFC systems are largely dictated by the fuel/water and thermal management components. Costs are often attributed to those associated with the membrane electrode assembly (MEA) and specifically platinum-based electrocatalysts, but other factors such as packaging and BoP also play a role. In this talk, we will present our efforts to develop bipolar membrane fuel cell (BMFC) technologies to address some of these shortcomings. The BMFC uses a hybrid of proton exchange membrane (PEM) and anion exchange membrane (PEM) materials such that there is at least one internal acid-alkaline membrane junction, or interface. Depending on the respective configuration, water generation or consumption will occur at the junction. Paul Kohl’s group has demonstrated how this junction can be (i) used to improving hydrogen/oxygen MEA performance at low relative humidity such that the need for external humidification in reduced, and (ii) integrated into low temperature DMFC MEAs [1-3]. Bipolar membrane configurations may additionally be used to adjust the respective anode and cathode chemistries (i.e., acid or alkaline) such that the electrochemical kinetics may be improved and/or the amount of platinum-based electrocatalysts may be reduced. The focus of this talk will be the modeling of the bipolar membrane electrolyte materials and the BMFC system that complement our ongoing experimental materials and systems development efforts. A specific focus will be placed on understanding the nature of the bipolar membrane junction and its influence on transport phenomena within the BMFC. The insights from this modeling effort on the utilization of this technology for the development of a BMFC based DMFC with improved water/fuel and thermal management will be discussed. Acknowledgments: KNG, JPM, and DC gratefully acknowledge support from the U.S. Department of the Army, U.S. Army Materiel Command, Research Development and Engineering Command, and U.S. Army Research Laboratory. JMA, LL, and PAK gratefully acknowledge support from the U.S. Department of the Army, Deputy Assistant Secretary of the Army (DASA) International Collaboration Program through contract no. W911NF-14-2-0008.

Electrospun Bipolar Membranes for Portable Fuel Cells

Shifting to high pH fuel cell operating environments could potentially lower the overall fuel cell costs by reducing or replacing noble metals with other electrocatalytically-active non-noble metal materials. Anion-exchange membranes (AEMs) with mobile OH- ions are one way to shift to higher pH environments, and have received attention for use in alkaline fuel cells.[1] Most AEMs studied to-date are organic and exhibit low chemical stabilities and low ionic conductivities (i.e. mobile transport ions are OH-, CO3 2- or mixed ion form) after prolonged exposure to high pH media and temperatures greater than 60°C.[2] A number of advancements have been made for increasing the ion-exchange group stability for reasonable ion-conductivities by using phenyl guanidinium-[3], imidazolium-[4] and other metal-cation exchange groups[5]. Park et al. recently demonstrated a novel approach for creating AEM membranes by electrospinning.[6] The electrospinning approach allows for short- and long-range fabrication, which is useful for proton- and/or hydroxide-transport membranes. In addition to the electrocatalyst and membrane materials concerns, fuel cells commonly employee auxiliary components to assist in balancing the water production and consumption at the anode and cathode compartments.[7] The auxiliary components cause the total fuel cell device (i.e. composed of stack and other components) to increase in size and weight. One way to reduce the logistics burden and overall balance of plant (BOP) is to design bipolar membranes that are comprised of an acid membrane component spatially separated from an alkaline membrane component. The bipolar membrane concept was recently demonstrated by Unlu et al.[8] The reduction in the BOP would therefore reduce the overall cost and size of the fuel cell device. In this study, we synthesize AEM and PEM precursors and subsequently co-electrospin these precursors into a bipolar membrane. The bipolar membrane produced may be potentially used for portable hybrid acid-alkaline fuel cells. The electrospun PEM component is primarily made of Nafion embedded in an inert matrix layer. The electrospun AEM component is comprised of a synthesized and subsequently modified polysulfone derivative embedded in an inert matrix layer. We provide physical characterizations such as TEM, SEM, BET, swelling and dimensional change measurements to understand each electrospun component at the PEM and AEM compartments. Moreover, we perform ex-situ ion-transport measurements for bulk conductivities of the isolated and combined components. Figure 1 shows a schematic of the electrospinning process whereby a rotating roll configuration with multiple high voltage power supplies is utilized for fabricating a co-electrospun bipolar membrane. An SEM image is shown for the AEM fiber mat component, which is typically placed at the cathode compartment. Acknowledgements We gratefully acknowledge the fuel cell team at the U.S. Army Research Laboratory. We acknowledge the U.S. Department of the Army and Army Materiel Command for funding and support.

Density Functional Theory Studies Combined with Experimental Investigations of the Oxygen Reduction Reaction on Fe- or Co-Containing Carbon Fibers

The oxygen reduction reaction (ORR) is responsible for a large potential loss for anion-exchange membrane fuel cells (AEMFCs), and researchers continue to develop non-Platinum-group-metal (non-PGM) electrocatalysts that attenuate the related kinetic losses. Moreover, it is desirable to use non-PGM electrocatalysts to mitigate fuel cell costs, and with respect to the ORR, AEMFCs provide an operating environment that allows a shift to non-PGM electrocatalysts.1,2 Many research investigations have been performed on non-PGM electrocatalysts such as M-phthalocyanines (MPc, where M = Fe, Co or Mn for example)3,4, heat-treated metal macrocycles5,6 and nitrogen-doped carbons devoid of metal nanoparticulates7. In some cases, these non-PGM electrocatalysts exhibit ORR activities comparable to Pt/C electrocatalysts. As a contribution to non-PGM electrocatalysts research efforts, we studied the ORR in 0.1N KOH at room temperature on Fe- or Co-carbon fibers derived by pyrolyzing electrospun nanofiber precursors. Electrospinning provides a facile approach for developing high-surface area carbon materials with a wide range of morphologies. However, as is the case with most heat-treated non-PGM electrocatalysts, the active site(s) for heat-treated metal-containing carbon materials are not well defined. Therefore, we combine our physical characterizations and electrochemistry findings with density functional theory (DFT) calculations and attempt to probe potential ORR pathways for Fe- or Co-N4-containing graphitic electrocatalyst clusters.We probe H2O, O2, HOOH, OOH, and OH adsorption on the Fe- and Co-containing graphitic clusters. In addition, we compare each of the adsorbate binding energies as a function of the spin and oxidation states. We also compare various DFT methods for each of the systems including M06-L, M062X and B3LYP. Lastly, we provide rotating ring disk electrode (RRDE) voltammetry, cyclic voltammetry and other physical characterizations such as XRD, XPS, TEM and SEM to better relate the electrocatalyst activity, morphology and surface chemistry to the DFT models developed. Figures 1 a-d show typical Fe- or Co-containing graphitic clusters used for the DFT calculations. Additional graphitic cluster configurations are considered and may be presented. Acknowledgements We gratefully acknowledge the fuel cell team at the U.S. Army Research Laboratory. We acknowledge the U.S. Department of the Army and Army Materiel Command for funding and support. The authors would also like to thank ARL for facilitating this opportunity through the Science, Mathematics and Research for Transformation (SMART) program.

The Occupational Health Partnership Program: A New Paradigm for Occupational Health Services

For a variety of reasons, occupational health services at Army Material Command installations became severely strained during the 1980s. The Occupational Health Partnership Program, developed to improve this support, describes control, responsibility, and cost sharing between Army Materiel Command and Army Medical Command. This innovative approach is finding new solutions to challenging problems. The authors describe the history, principles, status, and possible future of the partnership program.

U.S. Army battery needs-present and future

The purpose of this paper is to describe the needs of the U.S. Army for silent portable power sources, both in the near and longer term future. As a means of doing this, the programs of the Power Sources Division of the Army Research Laboratory are discussed. In carrying out these programs, the personnel of the Power Sources Division work closely with the Battery Management Office of the Army Materiel Command, which is located in the Logistics and Readiness Directorate of the Communication-Electronics Command (CECOM). We are also closely integrated with the Army Research Office, and the fuel cell personnel of the CECOM Research Development and Engineering Center (RDEC), and the battery personnel of the RDECs for the Tank and Automotive Command and the Missile Command. The six program areas discussed in which the Power Sources Division is engaged are: primary batteries, rechargeable batteries, reserve/fuze batteries, pulse batteries and capacitors, fuel cells, and thermophotovoltaic power generation.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Communications for the digitized battlefield of the 21st century

Technology base investments by the US Army will exploit the wealth of emerging commercial telecommunications services, as an operational supplement to classical tactical communications systems. This paper presents a series of technology components that collectively form the basis for the Army's Battlefield Information Transmission System and will provide the underlying seamless, global, "ubiquitous" transmission system for the Force XXI warfighter. The technical and system architectures of the 21st century will evolve through a gradual process of development, acquisition, and experimentation. This process, by definition, is a combined effort relying on the Army Materiel Command (AMC) Research, Development and Engineering Center (RDECs) working with the TRADOC battlelabs. The battlelabs, through a formal series of Advanced Warfighting Experiments (AWEs), play a crucial role in testing and adapting the technology produced by the AMC RDECs and commercial providers. Commercial technology is also directly exploited in TRADOC user environments as part of the Army's ACT II program.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

US Army Reliability Initiatives-In Concert with Air Force R&amp;M 2000

This paper describes how the US Army is improving readiness through enhanced reliability, availability, and maintainability (RAM). The Army is serious about supplying its personnel with the kind of equipment that stays on line. The US Army Materiel Command is taking aggressive steps to ensure that systems achieve their RAM requirements. Too often the Army has been accused of settling for minimum performance. As is well known, industry is reactive; it responds to pressure to improve what the customer thinks is important. An important step to getting higher levels of reliability and maintainability is to stand together with the Air Force and Navy customers and demand that RAM design and manufacturing disciplines are carried out and contractual RAM requirements are achieved. The achievement of requirements must be accomplished during system development and fielding. Improved RAM results in improved productivity, user satisfaction, and lower operating and support (O&S) costs. Linking R&M initiatives with O&S cost is an important step in justifying the up-front design and manufacturing disciplines that improve field performance. Meeting RAM requirements is the beginning and not the end of Army reliability efforts. Continued efforts to improve RAM are the thrust. For each system, the Army strives for continued improvement. Increased reliability reduces O&S costs while improving fielded mission accomplishment. Contractors will continue their efforts to improve production quality and to eliminate systemic causes of field failures.

Liquid Chromatographic Analysis of Hydraulic Fluids

Abstract Liquid chromatographic test methods are developed to fingerprint hydraulic fluids and to quantitatively analyze specific fluid components. Petroleum-base and synthetic hydrocarbon-base hydraulic fluids conforming to existing Military Specifications and used by the Army Materiel Command are considered. Detailed methods and test procedures are developed for the analysis of a MIL-H-6083D hydraulic fluid. The precision and accuracy of each method is evaluated.

Army materiel command planning principles and philosophy

This paper is intended to provide both experienced and inexperienced planners with a common understanding of the underlying philosophy and fundamental concepts of the U. S. Army Materiel Command (AMC) research and development (R&D) planning structure and technical planning processes. It should also assist executives engaged in the management of R&D programs to understand the rationale of R&D technical planning as a means toward improving the quality of decisions in the face of the difficult constraints and uncertainties inherent in the R&D field.

The Yuma Test Station, Arizona, hourly and daily insolation record, 1951–1962 : Bennett, Iven, U. S. Army Natick Laboratories, Natick, Mass., U. S. Army Materiel Command, Technical Report ES-15, March 1965, 57 p. illus.

The objective of this work is to verify the attenuation caused by atmospheric constituents through the relationship between global, direct and diffuse solar radiation with respect to optical air mass. The optical air mass change has spatial and temporal dependence and influences the radiation flux incident, causing changes in the average values. Global, diffuse and direct solar irradiances were provided by the Laboratory of Solar Radiometry of Botucatu-UNESP (latitude 22.9° South, longitude 48.45° West, altitude 745 m). The period assigned for the study comprised the years 2002 to 2006. The global solar radiation was measured by an Eppley PSP pyranometer. The direct solar radiation was measured by an Eppley Nip pyrheliometer attached to a ST-3 solar tracking system. The diffuse solar radiation was calculated by the difference between global and direct solar radiations. It was observed a decrease of solar radiation with the increase of optical air mass justified by the increase in probability of collision of solar rays with atmospheric constituents. For global solar radiation and optical air mass mo = 1, it was observed a minimum at 3.1 MJ/m2 and a maximum of 4.1 MJ/m2. For optical air mass mo=2, minimum at 1.5 MJ/m2 and a maximum of 1.9 MJ/m2. For direct solar radiation and optical air mass mo = 1, it was observed a minimum at 2 MJ/m2 and a maximum of 3.8 MJ/m2. For optical air mass mo=2, minimum at 1 MJ/m2 and a maximum of 1.5 MJ/m2. For diffuse solar radiation and optical air mass mo = 1, it was observed a minimum at 0.1 MJ/m2 and a maximum of 1.5 MJ/m2. For optical air mass mo=2, minimum at 0.1 MJ/m2 and a maximum of 0.8 MJ/m2. The joint analysis of data from direct and diffuse solar radiation allowed better understand of the attenuation process caused by the atmosphere, establishing qualitative relationships between absorption, scattering and reflection processes.

Planning, Installing, and Controlling The United States Army Materiel Command Management Information System.

Before discussing the planning, installation, and control of an information system for Army Materiel Command, a few words of introduction concerning the AMC mission and organization appear to be in order. The Army Materiel Command came into being in August 1962 with the implementation of the Army reorganization plan. This plan discontinued the Technical Service organizations which you may remember as Ordnance, Quartermaster, Signal, and so on. These Technical Services were responsible for the conceptual development of their assigned material items, the research and development leading to production and procurement of such new items, and the supply and maintenance of these items. In addition, in their particular technical skills they trained troops and performed the related personnel management functions. The CONARC, which as part of its mission conducted the training for the Combat Army, was assigned the total Army training mission. A new Department of the Army Staff Agency of Office of Personnel Operatio...