Structural Analysis of Sandwich Foam Panels

This article examines 582 cooperative research and development agreements (CRDAs) between federal (Air Force) agencies and other partners. Those CRDAs that exchange technology in novel phases of development tend to be long in duration relative to agreements that share mature technology. While novel projects could just take longer to complete, the findings also suggest that holdup risks increase in novelty. The geographic proximity of partners also affects CRDA duration positively, which is consistent with higher levels of tacit technology exchange. Repeat CRDAs tend to be shorter in duration, which is evidence of reputation effects. Duration of CRDAs decreases over time, which supports the argument that organizational form familiarity reduces the risks of negotiating agreements. In addition, CRDAs complement other modes of governance and methods to finance innovation. Cooperative research and development agreements with for‐profit partners are nearly 50 percent shorter than those with nonprofit p...

Application of dynamic analysis and modelling of structural concrete insulated panels (SCIP) for energy efficient buildings in seismic prone areas

Thermal insulation performance of GFRP squared tube reinforced sandwich panel

Researchers at the Department of Energy (DOE) facilities at Oak Ridge perform a variety of basic and applied research involving lasers and laser technology. One of the major strengths at Oak Ridge is the combination of core capabilities in optical materials, optical diagnostics, and sensors. Communities benefiting from these core capabilities include environmental, biomedical, and industrial sponsors. Industry can interact with Oak Ridge in a variety of ways; with Cooperative Research and Development Agreements (CRADAs), through Work for Others (WFO) programs, and as User Center participants. Oak Ridge is also active in sponsoring workshops and symposia for industrial participants like the recently held (December 1993) “Optical Diagnostics in Manufacturing and Process Control” symposium. In this paper, an overview of a selection of laser technologies residing at Oak Ridge is provided. Examples of the application of these technologies are given as well as overviews of several on-going CRADAs with industrial partners.

Since the late 1980s, the Cooperative Research and Development Agreement (CRADA) has been a prominent vehicle used to support collaboration between US federal laboratories and private firms. This paper examines the structure and goals of one of the most ambitious CRADAs conducted to date, the EUV CRADA, which involves three Department of Energy laboratories and leading US firms in the semiconductor industry and is aimed at the development of next-generation lithographic technologies. This large project is an important case study in ‘post-Cold-War’ technology policy and government-industry collaboration. Although the EUV project represents significant improvements in the design and management of CRADAs, it also illustrates the inherent difficulties of balancing political and economic goals in complex technology development programs.

This is a series of two papers in which the nonlinear stability behavior of sandwich panels is investigated. This part presents the buckling behavior and focuses on the critical load and the buckling mode. The buckling analysis is based on the extended high-order sandwich panel theory (EHSAPT) which takes transverse compressibility and axial rigidity of the core into account. It allows for the interaction between the faces and the core. The geometric nonlinearity, i.e., large displacement with moderate rotation, is considered in both faces and core. The weak form governing equations are derived based on the EHSAPT-based element. Detailed formulations and analysis procedures are provided. It presents a general approach for arbitrary buckling type without decoupling it into isolated global buckling and wrinkling. There are no additional assumptions made about the prebuckling state and buckling mode shape, which are commonly presumed in the literature. In addition, edge effects which are also commonly neglected are included. The prebuckling state is determined via a nonlinear static analysis. Solving an eigenvalue problem yields the critical load and the corresponding eigenvector gives the buckling mode. Sandwich panels with different lengths are studied as examples. Both global buckling and wrinkling are observed. It shows that the axial rigidity of the core has a pronounced effect on both the critical load and the buckling mode.

This Cooperative Research and Development Agreement (CRADA) has been a three-year collaboration among the Y-12 Plant Development Division, Blasch Precision Ceramics, Inc., and Surface Alloys, Inc. The purpose of the CRADA was to evaluate the production of a totally new crucible that would be noncarbon and that could perform like graphite. The effort required materials fabricated into a workable crucible. The goal was to produce a crucible that could be induction heated and allow melting of reactive metals without appreciable carbon contamination. The US Department of Energy programs involving casting uranium and its alloys have long been concerned with reducing deleterious carbon pickup that results from the use of graphite crucibles. Therefore, the results of this CRADA provide an alternative that can eliminate carbon pickup from the graphite crucible.

Because of the potential economic and safety benefits of the molten salt reactor (MSR) concept, development of several designs has been initiated around the world over the past decade. New international nuclear safeguards needs and verification challenges are likely to arise because of the commercial interests in MSRs and the number of MSR design variants. As a result, work was undertaken to explore the cross-cutting issues specific to the application of international nuclear safeguards (i.e., safeguards) to liquid-fueled molten salt reactors (LFMSRs). Through a public-private partnership, a report was developed that focuses on the TerraPower Molten Chloride Fast Reactor (MCFR) design that has received a funding award from the US Department of Energy (DOE), Office of Nuclear Energy. The report is intended to provide a preliminary analysis for a safeguards-by-design (SBD) effort to inform designers about how safeguards could be applied to LFMSRs by the International Atomic Energy Agency (IAEA).Although the report specifically focuses on the TerraPower design, the conclusions are applicable to the main design features of LFMSRs and can be used to extrapolate how existing IAEA safeguards measures for other fuel cycle facilities can be appropriately applied or modified. The report evaluates the appropriate safeguards approaches for LFMSRs, presents existing safeguards inspection technologies are still valid for LFMSRs, and identifies new challenges that will require novel measurement instruments to meet verification standards of the IAEA and the international safeguards regime. This document summarizes the results of the work performed under the full report developed as part of the Cooperative Research and Development Agreement (CRADA). This summary does not contain any protected CRADA information and is intended for public release.

: The term 'Cooperative Research and Development Agreement' means any agreement between one or more Federal laboratories and one or more non-Federal parties under which the Government, through its laboratories, provides personnel, services, facilities, equipment, or other resources with or without reimbursement (but not funds to non-Federal parties) and the non-Federal parties provide funds, personnel, services, facilities, equipment, or other resources toward the conduct of specified research or development efforts which are consistent with the missions of the laboratory; except that such term does not include a procurement contract or cooperative agreement as those terms are used in Sections 6303, 6304, and 6305 of Title 31, U.S. Code.

Background: Sandwich panels with low density core constructions are a class of structural elements with superior structural performance compared to traditional solid panels. Sandwich panels, compared to solid panels of equal mass, generally have much higher bending stiffness and comparable stretching stiffness, thus undergoing smaller deformation under loading. The potential advantage of sandwich panels for mitigating shock and projectile loading has been established in literature. The previous studies related to understanding the mechanics and structural performance of sandwich structures are mainly focused on studying the behavior of the core construction or the performance of a single isolated sandwich panel. These studies have provided significant insight into the behavior of sandwich panels, which includes mechanisms of energy dissipation in the core, stages of deformation of sandwich panels as they get impinged by an intense shock, fluid-structure effects for shock waves transmitted in air and water, and the mechanism of deformation and failure of sandwich panels under shock and projectile loading. Objective: This study extends previous research by exploring the behavior and structural performance of structural systems made of sandwich walled panels. The objective is to explore the potential benefit of sandwich configurations in enhancing the overall behavior of structural systems under complex loading conditions that could occur in petrochemical industry settings and pipeline networks. Method: We considered three frame structures, (i) frames made of solid panels (ii) frames with sandwich panel side walls and (iii) frames where all walls are made of sandwich panels. We also considered sandwich walled cylinders resembling pipes and compared their performance with the mechanical behavior of traditional pipes made of solid metal hollow cylinders. We used detailed finite element models to simulate the response of these structural systems. Results: The results showed that sandwich walled frame and cylinder (pipeline) configurations, in general, undergo smaller deflection than traditional counterpart structures under both quasi-static and high intensity dynamic (shock) loadings. Conclusions: The results highlight the potential of sandwich walled structural systems for developing novel threat resistant structures especially for the petrochemical industry and pipeline networks.

The use of polymeric and metallic foam sandwich panels in naval, aerospace, railway and automotive constructions is rapidly growing in the recent years because of technological improvements in manufacturing processes. However, it is still difficult to establish a direct relationship between the mechanical properties possessed by the panel and the specific manufacturing process. Mechanisms behind panel deformation, crack growth, fracture initiation and propagation still are not completely understood and therefore are intensively studied. In particular, structural behavior under compression is a critical issue also in view of the lack of official standards on foam core sandwich panels. This work aims at studying mechanical properties of high density polyethylene foam core sandwich panels produced by rotational molding. These panels can be built without using adhesives as the polyethylene foam grows inside mold and then adheres to facesheets while material still is at high temperature. In the present study, polyethylene foam panels of different thickness are tested under edgewise compression loading. The resulting out-of-plane deformation is then monitored in detail with a projection moire setup including two projectors and one camera.

Waste Management Inc. and the USEPA are jointly studying landfill bioreactors through a Cooperative Research and Development Agreement (CRADA) at the Outer Loop landfill in Louisville, KY. The study is evaluating two types of landfill bioreactor technology; aerobic-anaerobic and facultative. The aerobic-anaerobic landfill bioreactor (AALB) process being evaluated involves treating the waste aerobically for a short period followed by anaerobic operation. Duplicate six-acre AALB cells are being studied as they are being filled with waste. The waste density, measured as mass placed over volume consumed, has increased between 14 and 27 percent. Initial densities of 1400 to 1550 lbs/yd 3 have been increased to 1840 lbs/yd 3 in one case and 1560 lb/yd 3 in the other. The facultative landfill bioreactor (FLB) is designed to remove nitrogen from the landfill by external leachate nitrification followed by in situ denitrification of the treated leachate in the landfil. In 2000, a 5-year-old subtitle D landfill was retrofitted to evaluate the FLB process. Since liquid injection began in 2001, the waste density in the FLB has increased by 120 lbs/yd 3 to 1620 lbs/yd 3 . Verification of changes in the municipal solid waste (MSW) has been performed by collecting and analyzing samples of the waste mass over the life of the project. Changes in the cellulose, volatile solids, biochemical methane potential and lignin content of the waste are consistent with the observed increase in density. While the study has at least two more years before the research agreement is complete, this initial work supports predictions that significant gains in airspace are attainable with bioreactor technology. The solid waste industry has projected airspace gains of as much as 30 percent over the life of a bioreactor project.

The Savannah River National Laboratory (SRNL) and Air Products and Chemicals, Inc. (AP) have established a Cooperative Research and Development Agreement (CRADA) to improve the properties of the slag material produced from MSW gasification. Air Products, Inc. (AP) is developing a technology that uses plasma-enhanced gasification to create syngas from Municipal Solid Waste (MSW), for the purpose of generating electricity at a large scale. This report documents SRNL’s conclusions from research to support AP’s objectives performed in conjunction with the CRADA No. CR-12-002. The overall objectives of this study were to define an acceptable composition range for producing a satisfactory slag product from MSW gasification.

Based on previous demonstrated success at fabricating 5 and 10 kW scale magnetic gearbox (MGB) prototypes, Emrgy and its partners (the project team) proposed to design and construct a 100 kW scale MGB with a 30:1 gear ratio for the low-head hydro applications. The Statement of Project Objectives included tasks covering: 1) Market Applicability; 2) Technical Metrics; 3) Design (initial); 4) Electromagnetic (EM) Load and Structural Analysis; 5) Modal Analysis; 6) Sealing Design and 7) Final Design during Budget Period 1. Budget Period 2 included tasks covering: 1) Materials Procurement and Test Plan Development; 2) Assembly; and 3) Testing. The Market Applicability study (Task 1) led to a clear conclusion and recommendation toward “Low Head” technologies for maximum market share of both New Stream Reach development as well as powering Non-Powered Dams. The findings of this study also identified the opportunity for a larger scale magnetic gearbox-based drive train as a function of increased torque, as opposed to increased speed. The Technical Metrics Study (Task 2) concluded a horizontal orientation was preferred, examined potential loss mechanisms, concluded that a Halbach Array1 magnetic design was preferred, established a 30:1 gear ratio as optimal, and established a power rating of 100 kW as optimal. The subsequent initial and final detailed design process included electro-magnetic (EM) load and structural analysis (Task 4), a Modal analysis (for vibration) (Task 5), and a sealing design (Task 6) to assure water impermeability. The final design package (Task 7) included 729 individual parts, 117 unique part numbers, and 15 assemblies. In order to facilitate procurement, the full bill of materials was broken down into several sub-components: 1) custom magnetic parts; 2) custom machined parts; 3) custom casted parts; and 4) commercial off the shelf (COTS) parts. The casted parts were fabricated by Oak Ridge National Laboratory (ORNL) via a Cooperative Research and Development Agreement (CRADA) with Emrgy and funded by the Advanced Manufacturing Office (AMO). The procurement effort (Task 8) ultimately covered three time periods based on challenges encountered in meeting the budgeted cost for the prototype. Following the first effort in the early stages of Budget Period 2 in 2017, a no-cost time extension was granted to seek alternative fabrication and procurement options. The project was re-booted in 2020 based on the new ORNL CRADA that would focus on five (5) of the more difficult and expensive parts using their advanced manufacturing expertise. Procurement efforts for the other custom machined parts resulted in quotations that still exceeded the budget by more than $100k. This was, in part, also due to the concurrent COVID-19 pandemic that caused both supply chain disruptions and labor shortages. As the project continued, pricing and availability degraded further. In Q2 FY’22, it was decided to not proceed with the fabrication of the prototype (Task 9) based on budgetary limitations. Outcomes included a full and detailed design of a 100 kW magnetic gearbox and associated indented bill of materials (BOM) and CAD drawings, a full assembly instruction manual with an associated BOM for materials necessary to support assembly, the fabrication of the double Halbach magnetic array for the rotor/stator system, fabrication of five (5) sand-casted/machined parts (via CRADA with ORNL) and an initial draft of a comprehensive testing plan. The most significant non-outcome was the actual fabrication and testing of the prototype gearbox based on budget limitations. Lessons learned included the need for an Application / Design / Cost trade analysis to better elucidate the cost potential of the MGB in the projected volumes anticipated for future demand. This would better establish the efficacy of the original cost target ($0.80/Watt) and/or the need for reconsideration of designs and applications. Likewise, additional consideration of the prototype nature of the gearbox – single use, short lifetime, etc. - either as a separate exercise or in place of the design process completed, to reduce the cost of the demonstration prototype device. Additionally, project continuity was cited as a significant risk based on the loss of the primary design engineering firm after Budget Period 1. A design analysis exercise was conducted at the conclusion of the project to identify potential areas for cost reduction. One concept considered was the removal of the inner ring of magnets (with associated changes in the outer ring magnets) to enable a horizontal collapse of the design. It was estimated this could reduce cost by 10-25% without impacting performance.

Cyclophosphamide and Fludarabine Conditioning Chemotherapy Induces a Key Homeostatic Cytokine Profile in Patients Prior to CAR T Cell Therapy