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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 523 records · Page 29

Results of tests in the NASA/LaRC 31 inch CFHT on an 0.010-scale model (32-OT) of the space shuttle configuration 3 to obtain hypersonic aerodynamic characteristics for second stage operation during nominal boost and the abort RTLS mode (IA58)

Tests were conducted to obtain hypersonic aerodynamic forces and moments on an 0.010-scale model of the space shuttle vehicle configuration 3. Hypersonic stability data were obtained from tests at Mach 10.3 and dynamic pressure of 150 psf for the integrated orbiter and external tank, orbiter alone, and external tank alone. The effects of solid plume simulation from the main propulsion system as well as elevon, aileron, and rudder deflections were also investigated.

Thornton, D. E.↗

Sixty years of aeronautical research, 1917-1977

The history of Langley Research Center and its contributions to solving problems related to flight over the past six decades is recounted. Technical innovations described include those related to air craft construction materials, jet and rocket propulsion, flight testing and simulation, wind tunnel tests, noise reduction, supersonic flight, air traffic control, structural analysis, computational aerodynamics, and fuel efficiency.

Anderton, D. A.↗

Aeronautics for the 21st century

An assessment is made of the development possibilities of aerospace vehicle materials and structures, propulsion, avionics, configurations, computerized simulation, and operational capabilities. The supersonic transports envisioned for the 21st century would incorporate advanced, high temperature material structural design techniques, and a variable-cycle engine technology capable of a 40 percent increase in cruise efficiency over current systems, combined with low takeoff noise and efficient subsonic operation. This technology, as well as that of tilt-rotor VTOL aircraft which will be able to cruise at speeds comparable to those of present fixed-wing aircraft, are directly applicable to military systems. The impact of microelectronics and computer technologies on both avionics and the computational simulation of three-dimensional aerodynamic characteristics are also noted as important prospective developments.

Beggs, J. M.↗

Aeronautical facilities assessment

A survey of the free world's aeronautical facilities was undertaken and an evaluation made on where the relative strengths and weaknesses exist. Special emphasis is given to NASA's own capabilities and needs. The types of facilities surveyed are: Wind Tunnels; Airbreathing Propulsion Facilities; and Flight Simulators

Penaranda, F. E.↗

The lightcraft project

Rensselaer Polytechnic Institute has been developing a transatmospheric 'Lightcraft' technology which uses beamed laser energy to propel advanced shuttle craft to orbit. In the past several years, Rensselaer students have analyzed the unique combined-cycle Lightcraft engine, designed a small unmanned Lightcraft Technology Demonstrator, and conceptualized larger manned Lightcraft - to name just a few of the interrelated design projects. The 1990-91 class carried out preliminary and detailed design efforts for a one-person 'Mercury' Lightcraft, using computer-aided design and finite-element structural modeling techniques. In addition, they began construction of a 2.6 m-diameter, full-scale engineering prototype mockup. The mockup will be equipped with three robotic legs that 'kneel' for passenger entry and exit. More importantly, the articulated tripod gear is crucial for accurately pointing at, and tracking the laser relay mirrors, a maneuver that must be performed just prior to liftoff. Also accomplished were further design improvements on a 6-inch-diameter Lightcraft model (for testing in RPI's hypersonic tunnel), and new laser propulsion experiments. The resultant experimental data will be used to calibrate Computational Fluid Dynamic (CFD) codes and analytical laser propulsion models that can simulate vehicle/engine flight conditions along a transatmospheric boost trajectory. These efforts will enable the prediction of distributed aerodynamic and thruster loads over the entire full-scale spacecraft.

Messitt, Don G.↗

A comparison of paper and computer procedures in a Shuttle flight environment

The Electronic Procedures Experiment (EPROC) was flown as part of the Human Factors Assessment (HFA) experiment aboard the SpaceHab-1/STS-57 mission. EPROC is concerned with future, longer-duration missions which will increasingly rely on electronic procedures since they are more easily launched, updated in-flight, and offer automatic or on-request capabilities not available with paper. A computer-based task simulating a Space Station Propulsion System task was completed by one crewmember. The crewmember performed the task once using paper and once using computer procedures. A soldering and desoldering task was performed by another crewmember. Soldering was completed with paper procedures and desoldering was completed using computer procedures. Objective data was collected during each task session from the computer programs, videotapes, and crew notations in the paper and computer procedures. After each task session, subjective data was collected through the use of a computer-based questionnaire program. Resultant recommendations will be made available to future designers of electronic procedures systems for manned-space missions and other related uses.

Michael O'Neal↗

The lift-fan aircraft: Lessons learned

This report summarizes the highlights and results of a workshop held at NASA Ames Research Center in October 1992. The objective of the workshop was a thorough review of the lessons learned from past research on lift fans, and lift-fan aircraft, models, designs, and components. The scope included conceptual design studies, wind tunnel investigations, propulsion systems components, piloted simulation, flight of aircraft such as the SV-5A and SV-5B and a recent lift-fan aircraft development project. The report includes a brief summary of five technical presentations that addressed the subject The Lift-Fan Aircraft: Lessons Learned.

Deckert, Wallace H.↗

Demonstration of a High-Fidelity Predictive/Preview Display Technique for Telerobotic Servicing in Space

A highly effective predictive/preview display technique for telerobotic servicing in space under several seconds communication time delay has been demonstrated on a large laboratory scale in May 1993, involving the Jet Propulsion Laboratory as the simulated ground control station and, 2500 miles away, the Goddard Space Flight Center as the simulated satellite servicing set-up. The technique is based on a high-fidelity calibration procedure that enables a high-fidelity overlay of 3-D graphics robot arm and object models over given 2-D TV camera images of robot arm and objects. To generate robot arm motions, the operator can confidently interact in real time with the graphics models of the robot arm and objects overlaid on an actual camera view of the remote work site. The technique also enables the operator to generate high-fidelity synthetic TV camera views showing motion events that are hidden in a given TV camera view or for which no TV camera views are available. The positioning accuracy achieved by this technique for a zoomed-in camera setting was about +/-5 mm, well within the allowable +/-12 mm error margin at the insertion of a 45 cm long tool in the servicing task.

Kim, Won S.↗

Progress In Incompressible Pump Flow Calculations

Steady and unsteady flows for propulsion systems are efficiently simulated by solving the incompressible Navier-Stokes equations. The solution method is based on the pseudo compressibility approach and uses an implicit-upwind differencing scheme together with the Gauss-Seidel line relaxation method. Current computations use one equation Baldwin-Barth turbulence model which is derived from a simplified form of the standard kappa - epsilon model equations. The resulting computer code is applied to the flow analysis inside an advanced rocket pump impeller in steadily rotating reference frames. Numerical results are compared with experimental measurements. The effects of exit and shroud cavities with the leak-age flow are investigated. Time-accurate incompressible Navier-Stokes formulation with the overlapped grid scheme capability was evaluated by using MIT flapping foil experiment. The grid dependency, turbulence model effects, and the effect of order of differencing were investigated. Numerical results were compared against experimental data. The resulting procedure were applied to unsteady flapping foil calculations. Two upstream NACA 0025 foils perform high frequency synchronized motion and generate unsteady flow conditions to the downstream larger stationary foil. Comparison between unsteady experimental data and numerical results from two different moving boundary procedures will be presented.

Kiris, Cetin↗

Design Development Analyses in Support of a Heatpipe-Brayton Cycle Heat Exchanger

One of the power systems under consideration for nuclear electric propulsion or as a planetary surface power source is a heatpipe-cooled reactor coupled to a Brayton cycle. In this system, power is transferred from the heatpipes to the Brayton gas via a heat exchanger attached to the heatpipes. This paper discusses the fluid, thermal and structural analyses that were performed in support of the design of the heat exchanger to be tested in the SAFE-100 experimental program at Marshall Space Flight Center. A companion paper, "Mechanical Design and Fabrication of a SAFE-100 Heat Exchanger for use in NASA s Advanced Propulsion Thermal-hydraulic Simulator", presents the fabrication issues and prototyping studies that, together with these analyses, led to the development of this heat exchanger. An important consideration throughout the design development of the heat exchanger was its capability to be utilized for higher power and temperature applications. This paper also discusses this aspect of the design and presents designs for specific applications that are under consideration.

Steeve, Brian↗

Design Development Analyses in Support of a Heatpipe-Brayton Cycle Heat Exchanger

One of the power systems under consideration for nuclear electric propulsion or as a planetary surface power source is a heatpipe-cooled reactor coupled to a Brayton cycle. In this system, power is transferred from the heatpipes to the Brayton gas via a heat exchanger attached to the heatpipes. This paper discusses the fluid, thermal and structural analyses that were performed in support of the design of the heat exchanger to be tested in the SAFE-100 experimental program at Marshall Space Flight Center. A companion paper, "Mechanical Design and Fabrication of a SAFE-100 Heat Exchanger for use in NASA s Advanced Propulsion Thermal-hydraulic Simulator", presents the fabrication issues and prototyping studies that, together with these analyses, led to the development of this heat exchanger. An important consideration throughout the design development of the heat exchanger was its capability to be utilized for higher power and temperature applications. This paper also discusses this aspect of the design and presents designs for specific applications that are under consideration.

Steeve, Brian↗

Numerical Simulation of One-and Two-Phase Flows in Propulsion Systems

In this report, we present some results of problems investigated during joint research between the Hampton University Fluid Mechanics and Acoustics Laboratory (FM&AL), NASA Glenn Research Center (GRC) and the Hyper-X Program of the NASA Langley Research Center (LaRC). The main areas of current scientific interest of the FM&AL include an investigation of the proposed and patented advanced methods for aircraft engine thrust and noise benefits. These methods are based on nontraditional 3D corrugated and composite nozzle, inlet, propeller and screw designs such as the Bluebell and Telescope nozzles, Mobius-shaped screws, etc. These are the main subject of our other projects, of which one is the NASA MURED's FAR Award. Working jointly with this project team, our team also analyzes additional methods for exhaust jet noise reduction. These methods are without essential thrust loss and even with thrust augmentation.

Blankson, Isaiah M.↗

Constellation's First Flight Test: Ares I-X

On October 28, 2009, NASA launched Ares I-X, the first flight test of the Constellation Program that will send human beings to the Moon and beyond. This successful test is the culmination of a three-and-a-half-year, multi-center effort to design, build, and fly the first demonstration vehicle of the Ares I crew launch vehicle, the successor vehicle to the Space Shuttle. The suborbital mission was designed to evaluate the atmospheric flight characteristics of a vehicle dynamically similar to Ares I; perform a first stage separation and evaluate its effects; characterize and control roll torque; stack, fly, and recover a solid-motor first stage testing the Ares I parachutes; characterize ground, flight, and reentry environments; and develop and execute new ground hardware and procedures. Built from existing flight and new simulator hardware, Ares I-X integrated a Shuttle-heritage four-segment solid rocket booster for first stage propulsion, a spacer segment to simulate a five-segment booster, Peacekeeper axial engines for roll control, and Atlas V avionics, as well as simulators for the upper stage, crew module, and launch abort system. The mission leveraged existing logistical and ground support equipment while also developing new ones to accommodate the first in-line rocket for flying astronauts since the Saturn IB last flew from Kennedy Space Center (KSC) in 1975. This paper will describe the development and integration of the various vehicle and ground elements, from conception to stacking in KSC s Vehicle Assembly Building; hardware performance prior to, during, and after the launch; and preliminary lessons and data gathered from the flight. While the Constellation Program is currently under review, Ares I-X has and will continue to provide vital lessons for NASA personnel in taking a vehicle concept from design to flight.

Davis, Stephan R.↗

Coronagraph Focal-Plane Phase Masks Based on Photonic Crystal Technology: Recent Progress and Observational Strategy

Photonic crystal, an artificial periodic nanostructure of refractive indices, is one of the attractive technologies for coronagraph focal-plane masks aiming at direct imaging and characterization of terrestrial extrasolar planets. We manufactured the eight-octant phase mask (8OPM) and the vector vortex mask (VVM) very precisely using the photonic crystal technology. Fully achromatic phase-mask coronagraphs can be realized by applying appropriate polarization filters to the masks. We carried out laboratory experiments of the polarization-filtered 8OPM coronagraph using the High-Contrast Imaging Testbed (HCIT), a state-of-the-art coronagraph simulator at the Jet Propulsion Laboratory (JPL). We report the experimental results of 10-8-level contrast across several wavelengths over 10% bandwidth around 800nm. In addition, we present future prospects and observational strategy for the photonic-crystal mask coronagraphs combined with differential imaging techniques to reach higher contrast. We proposed to apply a polarization-differential imaging (PDI) technique to the VVM coronagraph, in which we built a two-channel coronagraph using polarizing beam splitters to avoid a loss of intensity due to the polarization filters. We also proposed to apply an angular-differential imaging (ADI) technique to the 8OPM coronagraph. The 8OPM/ADI mode avoids an intensity loss due to a phase transition of the mask and provides a full field of view around central stars. We present results of preliminary laboratory demonstrations of the PDI and ADI observational modes with the phase-mask coronagraphs.

coronagraphy↗

Improved Mars Helicopter Aerodynamic Rotor Model for Comprehensive Analyses

The Mars Helicopter is part of the NASA Mars 2020 rover mission scheduled to launch in July of 2020. Its goal is to demonstrate the viability and potential of heavier-than-air vehicles in the Martian atmosphere. Ultimately, it aims to bridge the resolution gap between orbiters and the rover as well as allow access to otherwise inaccessible regions. The low density of the Martian atmosphere and the relatively small-scale rotor result in very low Reynolds number flows. The low density and low Reynolds numbers reduce the lifting force and lifting efficiency, respectively. This paper describes the generation of the improved Mars Helicopter aerodynamic rotor model. The goal is to generate a performance model for the Mars Helicopter rotor using a free wake analysis, since this has a low computational cost for design. The improvements in the analysis are two-fold and are expanded on from two prior publications. First, the fidelity of the simulations is increased by performing higher-order two-dimensional time-accurate OVERFLOW simulations allowing for higher accuracy aerodynamic coefficients and a better understanding of the boundary layer behavior as well as its transient features. Second, a version of the model is generated to duplicate the exact testing conditions in the 25-ft. diameter Space Simulator at the Jet Propulsion Laboratory, which allows for better correlation of rotor performance figures. Previous work correlated performance with that test, but did not consider the higher temperatures in the experiment compared to those of the Martian atmosphere. The higher temperatures in the experiment are expected to give conservative performance estimates, as they give rise to an increase in speed of sound and decrease in observed Reynolds numbers.

Analyses↗

Demonstration of A High-Fidelity Predictive/Preview Display Technique for Telerobotic Servicing in Space

A highly effective predictive/preview display technique for telerobotic servicing in space under several seconds communication time delay has been demonstrated on a large laboratory scale in May, 1993, involving the Jet Propulsion Laboratory as the simulated ground control station and, 2500 miles away, the Goddard Space Flight Center as the simulated satellite servicing set-up. The technique isbased on a high-fidelity calibration procedure that enables a high-fidelity overlay of 3-D graphics robot arm and object models over given 2-D TV camera images of robot arm and objects. Togenerate robot arm motions, the operator can confidently interact in real time with the graphics models of the robot arm and objects overlaid on an actual camera view of the remote work site. The technique also enables the operator to generate high-fidelity synthetic TV camera views showing motion events that are hidden in a given TV camera view or for which no TV camera views are available...

Bejczy, A. K.↗

Improved Mars Helicopter Aerodynamic Rotor Model for Comprehensive Analyses

The Mars Helicopter is part of the NASA Mars 2020 rover mission scheduled to launch in July of 2020. Its goal is to demonstrate the viability and potential of heavier-than-air vehicles in the Martian atmosphere. Ultimately, it aims to bridge the resolution gap between orbiters and the rover as well as allow access to otherwise inaccessible regions. The low density of the Martian atmosphere and the relatively small-scale rotor result in very low Reynolds number flows. The low density and low Reynolds numbers reduce the lifting force and lifting efficiency, respectively. This paper describes the generation of the improved Mars Helicopter aerodynamic rotor model. The goal is to generate a performance model for the Mars Helicopter rotor using a free wake analysis, since this has a low computational cost for design. The improvements in the analysis are two-fold and are expanded on from two prior publications. First, the fidelity of the simulations is increased by performing higher-order two-dimensional time-accurate OVERFLOW simulations allowing for higher accuracy aerodynamic coefficients and a better understanding of the boundary layer behavior as well as its transient features. Second, a version of the model is generated to duplicate the exact testing conditions in the 25–ft. diameter Space Simulator at the Jet Propulsion Laboratory, which allows for better correlation of rotor performance figures. Previous work correlated performance with that test, but did not consider the higher temperatures in the experiment compared to those of the Martian atmosphere. The higher temperatures in the experiment are expected to give conservative performance estimates, as they give rise to an increase in speed of sound and decrease in observed Reynolds numbers.

Grip, Håvard F.↗