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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
NASA NTRS2004

Main Power Distribution Unit for the Jupiter Icy Moons Orbiter (JIMO)

Around the year 2011, the Jupiter Icy Moons Orbiter (JIMO) will be launched and on its way to orbit three of Jupiter s planet-sized moons. The mission goals for the JIMO project revolve heavily around gathering scientific data concerning ingredients we, as humans, consider essential: water, energy and necessary chemical elements. The JIM0 is an ambitious mission which will implore propulsion from an ION thruster powered by a nuclear fission reactor. Glenn Research Center is responsible for the development of the dynamic power conversion, power management and distribution, heat rejection and ION thrusters. The first test phase for the JIM0 program concerns the High Power AC Power Management and Distribution (PMAD) Test Bed. The goal of this testing is to support electrical performance verification of the power systems. The test bed will incorporate a 2kW Brayton Rotating Unit (BRU) to simulate the nuclear reactor as well as two ION thrusters. The first module of the PMAD Test Bed to be designed is the Main Power Distribution Unit (MPDU) which relays the power input to the various propulsion systems and scientific instruments. The MPDU involves circuitry design as well as mechanical design to determine the placement of the components. The MPDU consists of fourteen relays of four different variations used to convert the input power into the appropriate power output. The three phase system uses 400 Vo1ts(sub L-L) rms at 1000 Hertz. The power is relayed through the circuit and distributed to the scientific instruments, the ION thrusters and other controlled systems. The mechanical design requires the components to be positioned for easy electrical wiring as well as allowing adequate room for the main buss bars, individual circuit boards connected to each component and power supplies. To accomplish creating a suitable design, AutoCAD was used as a drafting tool. By showing a visual layout of the components, it is easy to see where there is extra room or where the components may interfere with one another. By working with the electrical engineer who is designing the circuit, the specific design requirements for the MPDU were determined and used as guidelines. Space is limited due to the size of the mounting plate therefore each component must be strategically placed. Since the MPDU is being designed to fit into a simulated model of the spacecraft systems on the JIMO, components must be positioned where they are easily accessible to be wired to the other onboard systems. Mechanical and electrical requirements provided equally important limits which are combined to produce the best possible design of the MPDU.

Papa, Melissa R.↗
DOE OSTI2022

Novel Tube Design for Superheater Heat Exchanger Enabled Via Additive Manufacturing

Superheater tubes are critical boiler components that operate at relatively higher temperatures and pressure. Amongst the primary concerns for these tubes is the deposition of ash particles on the tube surface, leading to the reduced thickness of the tube due to material corrosion, consequently causing early creep failure of the component. In this research, a novel tube design has been proposed which resembles a teardrop or ogive shape to reduce the drag and concurrently improve the creep life of the superheater tubes. To administer the practicality of novel tubes, metal additive manufacturing (AM), for instance, laser-powder bed fusion (L-PBF), has been proposed. These unconventional designs were assessed and compared with the baseline circular tube design for mechanical design requirements (hoop stress and creep life) and the particle and flue gas flow characteristics around the differently shaped tubes. A thermomechanical finite element (FE) analysis was performed for hoop stress calculations. This study also emphasizes on effect of circumferential thermal variation on hoop stress distribution in tubes. Therefore, a detailed two-dimensional (2D) thermal simulation has been performed to report the circumferential thermal variation on the tube. A computational fluid dynamics (CFD) analysis coupled with particle tracing was performed for gas flow visualization and particle tracing around the proposed shapes and baseline circular-shaped tube design. The Schlieren optic setup was built and leveraged for qualitative validation of the proposed design. The complete design methodology established in the paper shows teardrop-shaped tubes better in terms of drag and creep life in contrast to the circular-shaped tube.

42 ENGINEERING↗
NASA NTRS1985

Bipolar nickel-hydrogen battery design

The initial design for the NASA-Lewis advanced nickel-hydrogen battery is discussed. Fabrication of two 10-cell boilerplate battery stacks will soon begin. The test batteries will undergo characterization testing and low Earth orbit life cycling. The design effectively deals with waste heat generated in the cell stack. Stack temperatures and temperature gradients are maintained to acceptable limits by utilizing the bipolar conduction plate as a heat path to the active cooling fluid panel external to the edge of the cell stack. The thermal design and mechanical design of the battery stack together maintain a materials balance within the cell. An electrolyte seal on each cell frame prohibits electrolyte bridging. An oxygen recombination site and electrolyte reservoir/separator design does not allow oxygen to leave the cell in which it was generated.

Koehler, C. W.↗
NASA NTRS1998

MIT-CSR XIS Project

This report outlines the proposers' progress toward MIT's contribution to the X-Ray Imaging Spectrometer (XIS) experiment on the Japanese ASTRO-E mission. The report discusses electrical system design, mechanical system design, and ground support equipment.

Source record↗
NASA NTRS2001

Highly Loaded Low Pressure Turbine (LPT)

The goal of this study is to evaluate aspirated and non-aspirated aerodynamics on highly loaded LPT design. The objective is to increase stage loading by 30 to 50 percent without loss of efficiency for an existing low pressure turbine design. A study conducted on a NASA highly loaded multistage fan drive turbine (NASA CR-1964) indicated that end-wall bleed at the hub is a more significant parameter compared to aspirated airfoil. Based on this study, a 3-stage LPT is redesigned to 2-stage LIT with and without end-wall bleed. Both aerodynamic design and mechanical design are completed. In addition to end-wall bleed, exit guide vanes are designed with aspirated airfoils to reduce the losses. The LPT is redesigned with all constraints necessary for practical application. The benefit of the high-performance, highly loaded LPT shows up in reduced stage and part count, reduced size and weight, and reduced cost.

Ortiz, Milt↗
NASA NTRS2017

Development of Reliable Life Support Systems

The life support systems on the International Space Station (ISS) are the culmination of an extensive effort encompassing development, design, and test to provide the highest possible confidence in their operation on ISS. Many years of development testing are initially performed to identify the optimum technology and the optimum operational approach. The success of this development program depends on the accuracy of the system interfaces. The critical interfaces include the specific operational environment, the composition of the waste stream to be processed and the quality of the product. Once the development program is complete, a detailed system schematic is built based on the specific design requirements, followed by component procurement, assembly, and acceptance testing. A successful acceptance test again depends on accurately simulating the anticipated environment on ISS. The ISS Water Recovery System (WRS) provides an excellent example of where this process worked, as well as lessons learned that can be applied to the success of future missions. More importantly, ISS has provided a test bed to identify these design issues. Mechanical design issues have included an unreliable harmonic drive train in the Urine Processor's fluids pump, and seals in the Water Processor's Catalytic Reactor with insufficient life at the operational temperature. Systems issues have included elevated calcium in crew urine (due to microgravity effect) that resulted in precipitation at the desired water recovery rate, and the presence of an organosilicon compound (dimethylsilanediol) in the condensate that is not well removed by the water treatment process. Modifications to the WRS to address these issues are either complete (and now being evaluated on ISS) or are currently in work to insure the WRS has the required reliability before embarking on a mission to Mars.

Carter, Layne↗
NASA NTRS2017

Development of Reliable Life Support Systems

The life support systems on the International Space Station (ISS) are the culmination of an extensive effort encompassing development, design, and test to provide the highest possible confidence in their operation on ISS. Many years of development testing are initially performed to identify the optimum technology and the optimum operational approach. The success of this development program depends on the accuracy of the system interfaces. The critical interfaces include the specific operational environment, the composition of the waste stream to be processed and the quality of the product. Once the development program is complete, a detailed system schematic is built based on the specific design requirements, followed by component procurement, assembly, and acceptance testing. A successful acceptance test again depends on accurately simulating the anticipated environment on ISS. The ISS Water Recovery System (WRS) provides an excellent example of where this process worked, as well as lessons learned that can be applied to the success of future missions. More importantly, ISS has provided a test bed to identify these design issues. Mechanical design issues have included an unreliable harmonic drive train in the Urine Processor's fluids pump, and seals in the Water Processor's Catalytic Reactor with insufficient life at the operational temperature. Systems issues have included elevated calcium in crew urine (due to microgravity effect) that resulted in precipitation at the desired water recovery rate, and the presence of an organosilicon compound (dimethylsilanediol) in the condensate that is not well removed by the water treatment process. Modifications to the WRS to address these issues are either complete (and now being evaluated on ISS) or are currently in work to insure the WRS has the required reliability before embarking on a mission to Mars.

Carter, Layne↗
NASA NTRS1975

An improved method for optimum design of mechanically and thermally loaded structures

The problem of obtaining the minimum-mass design of mechanically and thermally loaded structures is presented. The special nature of thermal stresses with regard to their response to resizing of structural members is discussed. It is shown that conventional resizing procedures which are based on driving the total stress to its allowable value may be inefficient when the thermal stress in an element makes up a significant fraction of the total stress. An improved algorithm for resizing of structures subjected to thermal stresses is treated. In this algorithm the mechanical portions of the stresses were driven to their maximum allowable values. The thermal stresses were used to adjust the allowable values of the mechanical stresses. The new algorithm was exercised for a number of truss structures of varying complexity and compared with ordinary fully stressed design.

Adelman, H. M.↗
NASA NTRS2002

ISS SGANT Group Level Offloading Test Mechanism

The International Space Station (ISS) Space-to-Ground Antenna (SGANT) is used for ISS communication with earth through the Tracking and Data Relay Satellite (TDRSS). Due to the different speeds of travel between earth, ISS and TDRSS, a steerable SGANT was required on the ISS. The mechanical design of SGANT is an unbalanced mechanism with insufficient strength and driving torque to support and drive itself in a 1G environment. For ground testing, a specially designed offloading mechanism is required. Basically, the test mechanism must offload the SGANT in a two-axis operation, allowing the SGANT to move within a specific range, speed and acceleration; therefore the SGANT can move from elevation 0 to 90 deg and be tested at both the 0 and 90 deg positions. The load introduced by the test equipment should be less than 10.17 N-m (7.5 ft-lbf). The on-ground group level tracking test is quite challenging due to the unbalanced antenna mechanical design and tough specification requirements. This paper describes the detailed design, fabrication, and calibration of the test mechanism, and how the above requirements are met. The overall antenna is simplified to a mass model in order to facilitate the offloading mechanism design and analysis. An actual SGANT mass dummy was made to calibrate the system. This paper brings together the theoretical analysis and the industrial experience that were relied upon to meet the above-mentioned requirements for the ground test. The lessons learned during the calibration phase are extremely important for future double or multiple offloading system designs. The ISS SGANT QM and FM units passed their ground test and the SGANT/Boom fit check successfully, and the Flight Model (FM) was delivered to SSPF in April 1998. It is now installed on ISS and functioning well.

Zhang, Xi-Lin↗
DOE OSTI2022

Computational design of mechanically coupled axle-rotor protein assemblies

Natural molecular machines contain protein components that undergo motion relative to each other. Designing such mechanically constrained nanoscale protein architectures with internal degrees of freedom is an outstanding challenge for computational protein design. Here we explore the de novo construction of protein machinery from designed axle and rotor components with internal cyclic or dihedral symmetry. We find that the axle-rotor systems assemble in vitro and in vivo as designed. Using cryo–electron microscopy, we find that these systems populate conformationally variable relative orientations reflecting the symmetry of the coupled components and the computationally designed interface energy landscape. These mechanical systems with internal degrees of freedom are a step toward the design of genetically encodable nanomachines.

Science & Technology - Other Topics↗
NASA NTRS2012

GMI Spin Mechanism Assembly Design, Development, and Test Results

The GMI Spin Mechanism Assembly (SMA) is a precision bearing and power transfer drive assembly mechanism that supports and spins the Global Microwave Imager (GMI) instrument at a constant rate of 32 rpm continuously for the 3 year plus mission life. The GMI instrument will fly on the core Global Precipitation Measurement (GPM) spacecraft and will be used to make calibrated radiometric measurements at multiple microwave frequencies and polarizations. The GPM mission is an international effort managed by the National Aeronautics and Space Administration (NASA) to improve climate, weather, and hydro-meteorological predictions through more accurate and frequent precipitation measurements [1]. Ball Aerospace and Technologies Corporation (BATC) was selected by NASA Goddard Space Flight Center (GSFC) to design, build, and test the GMI instrument. The SMA design has to meet a challenging set of requirements and is based on BATC space mechanisms heritage and lessons learned design changes made to the WindSat BAPTA mechanism that is currently operating on orbit and has recently surpassed 8 years of Flight operation.

Woolaway, Scott↗
NASA NTRS2002

NASA Space Mechanisms Handbook and Reference Guide Expanded Into CD-ROM Set

Several NASA missions suffered failures and anomalies due to problems in applying space mechanisms technology to specific projects. Research shows that engineers often lack either adequate knowledge of mechanism design or sufficient understanding of how mechanisms affect sensitive systems. The Space Mechanisms Project conducted a Lessons Learned study and published a Space Mechanisms Handbook to help space industry engineers avoid recurring design, qualification, and application problems. The Space Mechanisms Handbook written at the NASA Glenn Research Center details the state-of-the-art in space mechanisms design as of 1998. NASA's objective in developing this Space Mechanisms Handbook was to provide readily accessible information on such areas as space mechanisms design, mechanical component availability and use, testing and qualification of mechanical systems, and a listing of worldwide space mechanisms experts and testing facilities in the United States. This handbook has been expanded into a two-volume CD-ROM set in an Adobe Acrobat format. In addition to the handbook, the CD's include (1) the two volume Space Mechanisms Lessons Learned Study, (2) proceedings from all the NASA hosted Aerospace Mechanisms Symposia held through the year 2000, (3) the Space Materials Handbook, (4) the Lubrication Handbook for the Space Industry, (5) the Structural & Mechanical Systems Long-Life Assurance Design Guidelines, (6) the Space Environments and Effects Source-Book, (7) the Spacecraft Deployable Appendages manual, (8) the Fastener Design Manual, (9) A Manual for Pyrotechnic Design, Development and Qualification, (10) the Report on Alternative Devices to Pyrotechnics on Spacecraft, and (11) Gearing (a manual). In addition, numerous other papers on tribology and lubrication are included.This technical summary of the project provides information on how to obtain the handbook and related information.

Fusaro, Robert L.↗
NASA NTRS1981

Modular antenna design study

The mechanical design of a modular antenna concept was developed sufficiently to allow manufacture of a working demonstration model of a module, to predict mass properties, and to make performance estimates for antenna reflectors composed of these modules. The primary features of this concept are: (1) each module is an autonomous structural element which can be attached to adjacent modules through a three point connection; (2) the upper surface is a folding hexagonal truss plate mechanism which serves as the supporting structure for a reflective surface; and (3) the entire truss and surface can be folded into a cylindrical envelope in which all truss elements are essentially parallel. The kinematic studies and engineering demonstration model fully verified the deployment kinematics, stowing philosophy, and deployment sequencing for large antenna modules. It was established that such modules can be stowed in packages as small as 25 cm in diameter, using 1.27 cm diameter structural tubes. The development activity indicates that this deployable modular approach towards building large structures in space will support erection of 450 m apertures for operation up to 3 GHz with a single space shuttle flight.

Ribble, J. W.↗
NASA NTRS1971

Integral lift engine preliminary design

A preliminary mechanical design of a complete lift fan engine system is reported. A description of the lift fan engine, layout drawings of the components and complete engine, and a discussion of the design analyses and results are presented. The design features and areas of analysis include fan and compressor rotor blades of composite construction, a combustor folded over the compressor, relatively high-temperature blades in the high-pressure turbine, the first stage of the low-pressure turbine used for bearing support and ducting of lubricant to the bearings, a complete lubrication system, critical speeds of the shafting, and vibration and flutter of the blading.

Pratt, W.↗
NASA NTRS1976

Quiet Clean Short-haul Experimental Engine (QCSEE) Under-The-Wing (UTW) boiler plate nacelle and core exhaust nozzle design report

The mechanical design of the boiler plate nacelle and core exhaust nozzle for the QCSEE under the wing engine is presented. The nacelle, which features interchangeable hard-wall and acoustic panels, is to be utilized in the initial engine testing to establish acoustic requirements for the subsequent composite nacelle as well as in the QCSEE over the wing engine configuration.

Source record↗
NASA NTRS2011

Global Microwave Imager (GMI) Spin Mechanism Assembly Design, Development, and Performance Test Results

The GMI Spin Mechanism Assembly (SMA) is a precision bearing and power transfer drive assembly mechanism that supports and spins the Global Microwave Imager (GMI) instrument at a constant rate of 32 rpm continuously for the 3 year plus mission life. The GMI instrument will fly on the core Global Precipitation Measurement (GPM) spacecraft and will be used to make calibrated radiometric measurements at multiple microwave frequencies and polarizations. The GPM mission is an international effort managed by the National Aeronautics and Space Administration (NASA) to improve climate, weather, and hydro-meteorological predictions through more accurate and frequent precipitation measurements [1]. Ball Aerospace and Technologies Corporation (BATC) was selected by NASA Goddard Space Flight Center (GSFC) to design, build, and test the GMI instrument. The SMA design has to meet a challenging set of requirements and is based on BATC space mechanisms heritage and lessons learned design changes made to the WindSat BAPTA mechanism that is currently operating on-orbit and has recently surpassed 8 years of Flight operation.

Kubitschek, Michael↗
DOE OSTI2024

Final CRADA Report – NFE-21-08693

TAE Technologies is developing a magnetic fusion energy concept known as the beam-driven field-reversed configuration (FRC) with the ultimate goal of developing a reactor for commercial electricity production capable of burning aneutronic pB11 fuel. To achieve the high plasma temperatures this requires, auxiliary radiofrequency (RF) heating will likely be needed. High Harmonic Fast Wave (HHFW) heating has been identified as a candidate RF heating scheme to overcome the unique challenges posed to RF heating by the FRC, including the large distance from the plasma edge to the last closed flux surface and a magnetic field profile with strength decreasing from edge to core and reversing sign at a null point inside the plasma. The purpose of this project was to develop the experimental capabilities to test HHFW on TAE’s C-2W device through the design of a phased array antenna and accompanying matching network. The design was performed by ORNL and informed by experiments with a prototype four-strap phased antenna-array that was manufactured and installed on the LArge Plasma Device (LAPD) at UCLA and simulations conducted with the Petra-M code under the purview of a previous INFUSE grant. The ORNL team completed the conceptual design of the antenna and matching network which was then handed off to the TAE Mechanical Design team. The design was then iterated on to ensure changes to the mechanical design did not interfere with the RF performance. This process is now complete, and, with mechanical design in hand, TAE is proceeding with plans for final integration.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗