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MFC Transient Testing Capabilities and Fuel Fabrication capabilities are summarized in this slide deck. Slides are included for TREAT and TREAT capabilities, EFF, FASB, FMF, ZPPR, AFF, and the Fuels Fabrication Modernization Capability. First use of this slide deck is for presentation at Westinghouse Electric Corporation, but there will be other uses later.
In this paper, we present an overview of recent progress in the development of the NASA Macro-Fiber Composite (MFC) piezocomposite actuator device. This will include a brief history of the development of the MFC, a description of the standard manufacturing process used to fabricate MFC actuators, and a summary of ongoing MFC electromechanical characterization testing. In addition, we describe the development of a prototype single-crystal piezoelectric MFC device, and compare its performance with MFC actuator specimens utilizing conventional piezoceramic materials.
The Irradiated Material Properties Accelerated Characterization Test (IMPACT) series of experiments will irradiate three metallic fuel alloy specimens with embedded thermal conductivity probes in the Advanced Test Reactor (ATR). Metallic fuel alloys have long been under investigation for use in advanced reactors on account of their high thermal conductivity. Metallic fuel undergoes dramatic microstructural changes early in life due to fission gas swelling until ~2-3 at% burnup when pores interconnect, thus allowing fission gas to escape into the fuel pin plenum and swelling effectively ceases. The evolution of metallic fuel thermal conductivity during this early phase has never been successfully measured in situ. This experiment will be designed to use advances in measurement sciences to characterize how thermal transport properties evolve while in reactor. The IMPACT experiment consists of three metallic fuel rodlets with thermal conductivity probes axially centered within the fuel specimen. This presentation is an overview of the IMPACT-01 assembly process with a focus MFC fuel fabrication and experiment assembly steps.
Since their market introduction in 1995, fiber Bragg gratings (FBGs) have emerged as excellent means of measuring such parameters as strain and temperature. Distributed-grating sensing is particularly beneficial for such structural-health monitoring applications such as those of 'smart' structures or integrated vehicle health management in aerospace vehicles. Because of the variability of their output wavelengths, tunable lasers have become widely used as means of measuring FBGs. Several versions of a lightweight assembly for strain-tuning an FBG and dampening its vibrations have been constructed. The main components of such an assembly are one or more piezoelectric actuators, an optical fiber containing one or more Bragg grating(s), a Bragg-grating strain-measurement system, and a voltage source for actuation. The piezoelectric actuators are, more specifically, piezoceramic fiber composite actuators and, can be, still more specifically, of a type known in the art as macro-fiber composite (MFC) actuators. In fabrication of one version of the assembly, the optical fiber containing the Bragg grating(s) is sandwiched between the piezoelectric actuators along with an epoxy that is used to bond the optical fiber to both actuators, then the assembly is placed in a vacuum bag and kept there until the epoxy is cured. Bonding an FBG directly into an MFC actuator greatly reduces the complexity, relative to assemblies, that include piezoceramic fiber composite actuators, hinges, ferrules, and clamp blocks with setscrews. Unlike curved actuators, MFC actuators are used in a flat configuration and are less bulky. In addition, the MFC offers some vibration dampening and support for the optical fiber whereas, in a curved piezoelectric actuator assembly, the optical fiber is exposed, and there is nothing to keep the exposed portion from vibrating.
Abstract Microfibrillated cellulose (MFC) with reinforcing effects is a useful building block in the fabrication of flexible and thin supercapacitors. Herein, a hybrid tin oxide‐cellulose nanocomposite was hydrothermally produced and coated on MFC thin films to form a supercapacitor. The hybrid tin oxide‐cellulose thin films were structurally analyzed using scanning electrode microscopy, Fourier transform infrared spectroscopy and x‐ray diffraction. The cellulose thin film with the highest loading of hybrid tin oxide‐cellulose nanocomposite exhibited a specific capacitance of 225.88 F g −1 at 100 mV s −1 and 486.38 F g −1 at 20 mV s −1 in the three‐electrode electrochemical system. In addition, it revealed good cyclic stability up to 40 cycles run continuously with 95% cyclic retention. The high specific capacitance and superior cyclic stability could be related to the enhanced charge mobility and ion diffusion between the solid and electrolyte interface. The cellulose thin film coated with flower‐like hybrid nanocomposite showed great potential in energy storage.
A digitally programmable current-mode analog fuzzy membership function circuit (MFC) has been designed, simulated and fabricated in a 0.5 micro-m CMOS technology.
In a metal fiber composite (MFC) additive manufacturing (AM) method, a layer of polymer structures is deposited using a fused filament fabrication (FFF) printer assembly comprising at least one nozzle. Subsequently, an MFC printer assembly is used to embed a continuous metal fiber into one or more of the polymer structures of the layer. The embedding is achieved by heating the metal fiber and applying pressure to the metal fiber using an embedding surface of the MFC printer assembly. The heated metal fiber melts polymer adjacent thereto, thereby allowing the pressure to embed the metal fiber into the polymer structure. Using the MFC-AM method, various composite structures can be formed, such as novel heat exchangers that may otherwise be difficult or impossible to fabricate via other manufacturing techniques.
The use of piezoelectric devices has become widespread since Pierre and Jacques Curie discovered the piezoelectric effect in 1880. Examples of current applications of piezoelectric devices include ultrasonic transducers, micro-positioning devices, buzzers, strain sensors, and clocks. The invention of such lightweight, relatively inexpensive piezoceramic-fiber-composite actuators as macro fiber composite (MFC) actuators has made it possible to obtain strains and displacements greater than those that could be generated by prior actuators based on monolithic piezoceramic sheet materials. MFC actuators are flat, flexible actuators designed for bonding to structures to apply or detect strains. Bonding multiple layers of MFC actuators together could increase force capability, but not strain or displacement capability. Cylindrical piezoelectric fiber composite (CPFC) actuators have been invented as alternatives to MFC actuators for applications in which greater forces and/or strains or displacements may be required. In essence, a CPFC actuator is an MFC or other piezoceramic fiber composite actuator fabricated in a cylindrical instead of its conventional flat shape. Cylindrical is used here in the general sense, encompassing shapes that can have circular, elliptical, rectangular or other cross-sectional shapes in the planes perpendicular to their longitudinal axes.
Over the past decade, NASA Langley Research Center (LaRC) has developed several actuator packaging concepts designed to enhance the performance of commercial electroactive ceramics. NASA LaRC focused on properly designed actuator and sensor packaging for the following reasons, increased durability, protect the working material from the environment, allow for proper mechanical and electrical contact, afford "ready to use" mechanisms that are scalable, and develop fabrication methodology applicable to any active material of the same physical class. It is more cost effective to enhance or tailor the performance of existing systems, through innovative packaging, than to develop, test and manufacture new materials. This approach led to the development of several solid state actuators that include THUNDER, the Macrofiber Composite or (MFC) and the Radial Field Diaphragm or (RFD). All these actuators are fabricated using standard materials and processes derived from earlier concepts. NASA s fabrication and packaging technology as yielded, piezoelectric actuators and sensors that are easy to implement, reliable, consistent in properties, and of lower cost to manufacture in quantity, than their predecessors (as evidenced by their continued commercial availability.) These piezoelectric actuators have helped foster new research and development in areas involving computational modeling, actuator specific refinements, and engineering system redesign which led to new applications for piezo-based devices that replace traditional systems currently in use.
A. The Microreactor Applications Research Validation and Evaluation (MARVEL) reactor will offer experimental capabilities that are not currently available at DOE’s national laboratories. Idaho National Laboratory (INL), operated for the U.S. Department of Energy (DOE) by Battelle Energy Alliance, LLC (BEA) (Contractor hereafter) is procuring services for the design, analysis, fabrication, testing and delivery of a Secondary Coolant Equipment system (SCE). This specification contains the requirements for design, analysis, fabrication, testing and delivery of the SCE as described herein. The MARVEL reactor is a microreactor which uses eutectic sodium-potassium alloy (NaK) as a primary coolant. The primary coolant is circulated through four primary loops by natural convection of the coolant. In each loop is a closed well which will accommodate an intermediate heat exchanger (IHX) for extracting heat from the loop. These wells will be referred to in this specification as the “IHX wells.” It is intended for the IHX containment to also be filled with NaK. The MARVEL design team has determined that a Heat Extraction System (HES) using pumped NaK will be used to extract heat from the IHXs and deliver it to a downstream system for power generation or alternate process heat users. This Heat Extraction System will enable MARVEL operations including the ability to test, demonstrate, and address issues related to installation, startup, and operations. In addition, it will allow down-stream utilization of process heat for various uses. The objective of this specification is to develop the final design for the HES Secondary Coolant Equipment system (SCE) that will be used as the core of the HES. This system provides control of the NaK circulation between the MARVEL reactor and the subsequent process heat utilization systems. It does not include design of the Intermediate Heat Exchangers and piping inside the T-REXc pit in which the reactor is located. B. The MARVEL microreactor will be installed in the Transient Reactor Test Facility (TREAT) building in the Transient Reactor Test (TREAT) Micro-Reactor Experiment Cell (T-REXc) C. An INL Subcontractor has developed a conceptual design for this system per SPC-71145, referred to in that specification as the Process Heat Extraction System. SPC-71260 is based on the pumped NaK loop concept developed under SPC-71145. D. The SCE system design and (as option scope) fabrication shall be provided by the awardee of the subcontract (Subcontractor hereafter) pertaining to this Specification. Prior to shipment, the SCE will be fabricated, assembled, and tested at the Subcontractor’s facility. After successful completion of acceptance testing, the SCE and associated equipment will be shipped to the Materials and Fuels Complex (MFC) at the INL (Contractor’s Facility hereafter) to be installed by others in TREAT/T-REXc.
The research reported herein includes the fabrication of a tunable optical fiber Bragg grating (FBG) fiber ring laser (FRL)1 from commercially available components as a high-speed alternative tunable laser source for NASA Langley s optical frequency domain reflectometer (OFDR) interrogator, which reads low reflectivity FBG sensors. A Macro-Fiber Composite (MFC) actuator invented at NASA Langley Research Center (LaRC) was selected to tune the laser. MFC actuators use a piezoelectric sheet cut into uniaxially aligned rectangular piezo-fibers surrounded by a polymer matrix and incorporate interdigitated electrodes to deliver electric fields along the length of the piezo-fibers. This configuration enables MFC actuators to produce displacements larger than the original uncut piezoelectric sheet. The FBG filter was sandwiched between two MFC actuators, and when strained, produced approximately 3.62 nm of wavelength shift in the FRL when biasing the MFC actuators from 500 V to 2000 V. This tunability range is comparable to that of other tunable lasers and is adequate for interrogating FBG sensors using OFDR technology. Three different FRL configurations were studied. Configuration A examined the importance of erbium-doped fiber length and output coupling. Configuration B demonstrated the importance of the FBG filter. Configuration C added an output coupler to increase the output power and to isolate the filter. Only configuration C was tuned because it offered the best optical power output of the three configurations. Use of Plastic Optical Fiber (POF) FBG s holds promise for enhanced tunability in future research.
Although methods in the design-build-test life cycle of the synthetic biology field have grown rapidly, the expansion has been non-uniform. The design and build stages in development have seen innovations in the form of biological CAD and more efficient means for building DNA, RNA, and other biological constructs. The testing phase of the cycle remains in need of innovation. Presented will be both a theoretical abstraction of biological measurement and a practical demonstration of a microfluidics-based platform for characterizing synthetic biological phenomena. Such a platform demonstrates a design of additive manufacturing (3D printing) for construction of a microbial fuel cell (MFC) to be used in experiments carried out in space. First, the biocompatibility of the polypropylene chassis will be demonstrated. The novel MFCs will be cheaper, and faster to make and iterate through designs. The novel design will contain a manifold switchingdistribution system and an integrated in-chip set of reagent reservoirs fabricated via 3D printing. The automated nature of the 3D printing yields itself to higher resolution switching valves and leads to smaller sized payloads, lower cost, reduced power and a standardized platform for synthetic biology unit tests on Earth and in space. It will be demonstrated that the application of unit testing in synthetic biology will lead to the automatic construction and validation of desired constructs. Unit testing methodologies offer benefits of preemptive problem identification, change of facility, simplicity of integration, ease of documentation, and separation of interface from implementation, and automated design.
TRIPWIRE is a multi-modal system for containment verification in inaccessible radiological and nuclear waste repositories. The sensing modes are focused on radiation, electromagnetic and vibration. The radiation detection component has been developed over the last three years at Idaho National Laboratory (INL). This development has focused on the fabrication, characterization, and testing of long-length (greater than 10-m) plastic scintillating fibers. This fiscal year, the focus of TRIPWIRE has been on field testing and demonstration of the radiation sensing component in a relevant environment. After reviewing the static storage facilities at INL, the Radioactive Scrap Waste Facility (RSWF) south storage area outside the Materials and Fuels Complex (MFC) was selected due to its periodic changes in configuration and inventory. This report summarizes the research outcomes for the work performed in fiscal year (FY) 2023.
The performance and advantages of Piezocomposite Actuators are to provide a low cost, in-situ actuator/sensor that is flexible, low profile and high strain per volt performance in the same plane of poled voltage. This paper extends reported data for the performance of these Macrofiber Composite (MFC) Actuators to include 4 progressively narrower Intedigitized electrode configurations with several line widths and spacing ratios. Data is reported for max free strain, average strain per applied volt, poling (alignment of the electric dipoles of the PZT ceramic) voltage vs. strain and capacitance, time to poling voltage 95% saturation. The output strain per volt progressively increases as electrode spacing decreases, with saturation occurring at lower poling voltages. The narrowest spacing ratio becomes prone to voltage breakdown or short circuits limiting the spacing width with current fabrication methods. The capacitance generally increases with increasing poling voltage level but has high sensitivity to factors such as temperature, moisture and time from poling which limit its usefulness as a simple indicator. The total time of applied poling voltage to saturate or fully line up the dipoles in the piezoceramic was generally on the order of 5-20 seconds. Less sensitivity to poling due to the applied rate of voltage increase over a 25 to 500 volt/second rate range was observed.