Search NASA⌕ Search

SEARCH · Search NASA

Results for “component testing”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,099 records · Page 61

Finite element elastic-plastic-creep and cyclic life analysis of a cowl lip

Results are presented of elastic, elastic-plastic, and elastic-plastic-creep analyses of a test-rig component of an actively cooled cowl lip. A cowl lip is part of the leading edge of an engine inlet of proposed hypersonic aircraft and is subject to severe thermal loadings and gradients during flight. Values of stresses calculated by elastic analysis are well above the yield strength of the cowl lip material. Such values are highly unrealistic, and thus elastic stress analyses are inappropriate. The inelastic (elastic-plastic and elastic-plastic-creep) analyses produce more reasonable and acceptable stress and strain distributions in the component. Finally, using the results from these analyses, predictions are made for the cyclic crack initiation life of a cowl lip. A comparison of predicted cyclic lives shows the cyclic life prediction from the elastic-plastic-creep analysis to be the lowest and, hence, most realistic.

Arya, Vinod K.↗

Design of Sensors for Control of Closed Loop Life Support Systems

A brief summary is presented of a Engineering Design sequence, a cooperation between NASA-Kennedy and the University of Florida on the Controlled Environmental Life Support System (CELSS) program. Part of the class was devoted to learning general principles and techniques of design. The next portion of the class was devoted to learning to design, actually fabricating and testing small components and subsystems of a CELSS.

Source record↗

Structures technologies for the Precision Segmented Reflector (PSR)

The PSR program is a first step in the development and validation of increasingly more precise and larger size lightweight segmented reflector technology that might ultimately be used in space on projects such as the Large Deployable Reflector (LDR). The LDR is described, and objectives of the PSR are discussed. Requirements for the PSR, including structure dimensions and geometric constraints, mass characteristics, erectable and deployable concepts, truss surface precision, and thermal and dynamic characteristics are discussed along with gravity deflections, secondary support characteristics, and removable members. Analytical development and system- and component-level tests are outlined.

Satter, C. M.↗

Sensor deployment mechanism for Surfer satellite

A design is presented for a sensor-deployment mechanism to be used aboard the Surfer satellite, from which scientific instruments will be extended to study the earth ionosphere during the Space Shuttle Tether Experiment. The design discussed uses four folding arms to extend the radial sensors, as well as two storable tubular extendible members or spirally wound self-extending tube booms to project the axial sensors outward. The design solution chosen, a folding arm, is discussed in detail with attention to mechanical operation and component functions. Test program results are presented.

Dill, Robert↗

Broadband, Achromatic Twyman-Green Interferometer

Improved Twyman-Green interferometer used in wave-front testing optical components at wavelengths from 200 to 1,100 nm, without having to readjust focus when changing wavelength. Built to measure aberrations of light passing through optical filters. Collimating and imaging lenses of classical Twyman-Green configuration replaced by single spherical mirror. Field lens replaced by field mirror. Mirrors exhibit no axial chromatic aberration and made to reflect light efficiently over desired broad range of wavelengths.

Steimle, Lawrence J.↗

Advanced Rotorcraft Transmission (ART) program-Boeing helicopters status report

The Advanced Rotorcraft Transmission (ART) program is structured to incorporate key emerging material and component technologies into an advanced rotorcraft transmission with the intention of making significant improvements in the state of the art (SOA). Specific objectives of ART are: (1) Reduce transmission weight by 25 pct.; (2) Reduce transmission noise by 10 dB; and (3) Improve transmission life and reliability, while extending Mean Time Between Removal to 5000 hr. Boeing selected a transmission sized for the Tactical Tilt Rotor (TTR) aircraft which meets the Future Air Attack Vehicle (FAVV) requirements. Component development testing will be conducted to evaluate the high risk concepts prior to finalizing the advanced transmission configuration. The results of tradeoff studies and development test which were completed are summarized.

Lenski, Joseph W., Jr.↗

Boeing Helicopters Advanced Rotorcraft Transmission (ART) program status

A review is presented of a program structured to incorporate key emerging component and material technologies into an advanced rotorcraft transmission with the intent of making significant improvements in the state-of-the-art (SOA). The specific goals of this program include a reduction of transmission weight by 25 percent relative to SOA trends, a reduction of transmission noise by 10 dB relative to SOA, and improvment of transmission life and reliability while extending the mean time between removal to 5000 hours. Attention is given to comparisons and trade studies between transmission configurations, component development testing, improved bearing technology, and the aircraft selection process for the program.

Lenski, Joseph W., Jr.↗

Advanced Rotorcraft Transmission program - A status report

The work being conducted under the first phase of the joint Army/NASA Advanced Rotorcraft Transmission program is reviewed. The work includes the selection of the Tactical Tilt Rotor (TTR) system and the development plans for assessing advanced component technologies. The TTR drive-system arrangement is outlined, and the comparisons and trade studies of self-aligning bearingless planetary, split torque, and conventional single-stage planetary configurations are presented. The effects of transmission improvements are evaluated, and component development testing is discussed, including noise reduction by active force cancellation, hybrid bidirectional tapered roller bearings, and precision net forged spur gears.

Drago, Raymond J.↗

Development of a Fabry-Perot interferometer for rocket engine plume monitoring

The development of a lightweight, compact, high-resolution Fabry-Perot interferometer (FPI) based spectrometer capable of detecting the spectral signatures of eroding engine components during test and/or flight operations is discussed. FPI based spectrometers will be designed to be smaller and lighter than grating or prism type devices and to provide greater wavelength resolving capability. The FPI system seeks to combine the features of high line resolution, active background discrimination, smart digital signal processing, and rocket engine flight capability. The design, fabrication, and test of a breadboard FPI spectrometer have been completed and the breadboard instrument has clearly demonstrated the viability of the approach. The breadboard instrument design and test results are also presented.

Bickford, R. L.↗

Finite element elastic-plastic-creep and cyclic life analysis of a cowl lip

Results are presented of elastic, elastic-plastic and elastic-plastic-creep analyses of a test-rig component of an actively cooled cowl lip. A cowl lip is part of the leading edge of an engine inlet of proposed hypersonic aircraft and is subject to severe thermal loadings and gradients during flight. Values of stresses calculated by elastic analysis are well above the yield strength of the cowl lip material. Such values are highly unrealistic, and thus elastic stress analyses are inappropriate. The inelastic (elastic-plastic and elastic-plastic-creep) analyses produce more reasonable and acceptable stress and strain distributions in the component. Finally, using the results from these analyses, predictions are made for the cyclic crack initiation life of a cowl lip. A comparison of predicted cyclic lives shows the cyclic life prediction from the elastic-plastic-creep analysis to be the lowest and, hence, most realistic.

Arya, V. K.↗

Compact Optical Correlator

Optical cross-correlator indicates position of target (if any) in scene matching target encoded in matched filter. Size reduced by use of prisms to fold optical path. Device designed, assembled from commercial components, and tested to verify feasibility of miniaturization for eventual incorporation into navigational and/or control systems of autonomous vehicles. For example, aircraft equipped with optical correlator recognizes prescribed target and measures its position, so that it lands on target under automatic control.

Scholl, Marija S.↗

Derated ion thruster development status

A 30 cm diameter xenon ion thruster is under development at NASA to provide an ion propulsion option for auxiliary and primary propulsion on missions of national interest. Specific efforts include thruster design optimizations, component life testing and validation, vibration testing, and performance characterizations. Under this program, the ion thruster will be brought to engineering model development status. This paper discusses the activities and preliminary test results to develop a 30 cm engineering model thruster.

Patterson, Michael J.↗

Derated ion thruster development status

A 30 cm diameter xenon ion thruster is under development at NASA to provide an ion propulsion option for auxiliary and primary propulsion on missions of national interest. Specific efforts include thruster design optimizations, component life testing and validation, vibration testing, and performance characterizations. Under this program, the ion thruster will be brought to engineering model development status. The activities and preliminary test results to develop a 30 cm engineering model thruster are discussed.

Patterson, Michael J.↗

Performance of the NASA 30 cm Ion Thruster

A 30 cm diameter xenon ion thruster is under development at NASA to provide an ion propulsion option for missions of national interest, and is being proposed for use on the USAF/TRW Space Surveillance, Tracking and Autonomous Repositioning (SSTAR) platform to validate ion propulsion. The thruster incorporates innovations in design, materials, and fabrication techniques compared to those employed in conventional ion thrusters. Specific development efforts include thruster design optimizations, component life testing and validation, vibration testing, and performance characterizations. Under this test program, the ion thruster will be brought to engineering model development status. This paper discusses the performance and power throttling test data for the NASA 30 cm diameter xenon ion thruster over an input power envelope of 0.7 to 4.9 kW, and corresponding thruster lifetime expectations.

Patterson, Michael J.↗

Integrated model development for liquid fueled rocket propulsion systems

As detailed in the original statement of work, the objective of phase two of this research effort was to develop a general framework for rocket engine performance prediction that integrates physical principles, a rigorous mathematical formalism, component level test data, system level test data, and theory-observation reconciliation. Specific phase two development tasks are defined.

Santi, L. Michael↗

Global changes in biogeochemical cycles in response to human activities

The main objective of our research was to characterize biogeochemical cycles at continental and global scales in both terrestrial and aquatic ecosystems. This characterization applied to both natural ecosystems and those disturbed by human activity. The primary elements of interest were carbon and nitrogen and the analysis sought to quantify standing stocks and dynamic cycling processes. The translocation of major nutrients from the terrestrial landscape to the atmosphere (via trace gases) and to fluvial systems (via leaching, erosional losses, and point source pollution) were of particular importance to this study. Our aim was to develop the first generation of Earth System Models. Our research was organized around the construction and testing of component biogeochemical models which treated terrestrial ecosystem processes, aquatic nutrient transport through drainage basins, and trace gas exchanges at the continental and global scale. A suite of three complementary models were defined within this construct. The models were organized to operate at a 1/2 degree latitude by longitude level of spatial resolution and to execute at a monthly time step. This discretization afforded us the opportunity to understand the dynamics of the biosphere down to subregional scales, while simultaneously placing these dynamics into a global context.

Moore, Berrien, III↗

A New Tribological Test for Candidate Brush Seal Materials Evaluation

A new tribological test for candidate brush seal materials evaluation has been developed. The sliding contact between the brush seal wires and their mating counterface journal is simulated by testing a small tuft of wire against the outside diameter of a high speed rotating shaft. The test configuration is similar to a standard block on ring geometry. The new tester provides the capability to measure both the friction and wear of candidate wire and counterface materials under controlled loading conditions in the gram to kilogram range. A wide test condition latitude of speeds (1 to 27 m/s), temperatures (25 to 700 C), and loads (0.5 to 10 N) enables the simulation of many of the important tribological parameters found in turbine engine brush seals. This paper describes the new test rig and specimen configuration and presents initial data for candidate seal materials comparing tuft test results and wear surface morphology to field tested seal components.

Fellenstein, James A.↗

Fiber Optic Cable Assemblies for Space Flight 2: Thermal and Radiation Effects

Goddard Space Flight Center is conducting a search for space flight worthy fiber optic cable assemblies that will benefit all projects at all of the NASA centers. This paper is number two in a series of papers being issued as a result of this task to define and qualify space grade fiber optic cable assemblies. Though to qualify and use a fiber optic cable in space requires treatment of the cable assembly as a system, it is very important to understand the design and behavior of its parts. This paper addresses that need, providing information on cable components shrinkage testing and radiation testing results from recent experiments at Goddard Space Flight Center.

Ott, Melanie N.↗