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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 73 records · Page 4

TPSAS-NF1676L-33031-DND

Cryogenic high-Reynolds number testing has been in use for approximately 40 years. This reliable testing capability is used to more closely predict full-scale flight aerodynamics for improved accuracy in estimates of aircraft performance, stability, and loads. A technical course has been created to educate industry, institutional, and research professionals in the overview of cryogenic high-Reynolds number testing and its impact, the availability and accessibility of cryogenic testing and considerations in test planning an execution, and the discussion of other in-depth technical topics. This particular presentation supports a section relating to special data reduction and correction methods as they relate to high-Reynolds number cryogenic wind-tunnel testing.

Scott Goodliff↗

Cosmology without general relativity

Idealizations in cosmology with special theory of relativity - partitioned universe, microcosmic model, and similarity to Newtonian cosmology

RELATIVITY THEORY↗

Calculation of the transient motion of elastic airfoils forced by control surface motion and gusts

The time-domain equations of motion of elastic airfoil sections forced by control surface motions and gusts were developed for the case of incompressible flow. Extensive use was made of special functions related to the inverse transform of Theodorsen's function. Approximations for the special cases of zero stream velocity, small time, large and time are given. A numerical solution technique for the solution of the general case is given. Examples of the exact transient response of an airfoil are presented.

Balakrishnan, A. V.↗

NASA-Ames Summer High School Apprenticeship Research Program (SHARP)

The function of SHARP is to recognize high school juniors who have demonstrated unusually high promise for sucess in mathemtics and science. Twenty academically talented students who will be seniors in high school in September were chosen to participate in SHARP 83. Mentors were selected to provide students with first-hand experiences in a research and development environment in order that each student might try out his or her tentative professional career choice. Some special features of SHARP included field trips to private industries doing similar and related research, special lectures on topics of research here at ARC, individual and group counseling sessions, written research papers and oral reports, and primarily the opportunity to be exposed to the present frontiers in space exploration and research. The long-range goal of SHARP is to contribute to the future recruitment of needed scientists and engineers. This final report is summary of all the phases of the planning and implemenation of the 1983 Summer High School Apprenticeship Research Program (SHARP).

Powell, P.↗

Recent NASA handling qualities research

A comprehensive review of NASA research results documented since the mid-1960's and some recently completed programs on aircraft handling qualities are presented. In addition to handling qualities research pertaining to vehicle stability and control characteristics, investigations related to specialized piloting tasks, cockpit displays, and environmental factors are summarized. The background leading to NASA's handling qualities research activities is discussed, and programs that have received major emphasis are indicated. For general aviation aircraft, the survey includes investigations aimed at improving handling qualities by incorporating increasingly sophisticated stability augmentation and display systems, simplifying the approach and landing task for relatively inexperienced pilots, and establishing the basic effects of turbulence. Research on the specialized piloting problem of steeper instrument approaches for noise abatement and investigations with a representative first generation aircraft are reviewed in the section on subsonic jet transports. Supersonic cruise aircraft programs include a variety of simulation studies related to supersonic transport designs and flight tests with the XB-70 aircraft. Investigations of high angle of attack loss of control problems and a flight study of direct lift control utilization for formation flying and aerial refueling are discussed in the review of tactical military aircraft research.

Wasicko, R. J.↗

Overview of Code Verification

The verified code for the SIFT Executive is not the code that executes on the SIFT system as delivered. The running versions of the SIFT Executive contain optimizations and special code relating to the messy interface to the hardware broadcast interface and to packing of data to conserve space in the store of the BDX930 processors. The running code was in fact developed prior to and without consideration of any mechanical verification. This was regarded as necessary experimentation with the SIFT hardware and special purpose Pascal compiler. The Pascal code sections cover: the selection of a schedule from the global executive broadcast, scheduling, dispatching, three way voting, and error reporting actions of the SIFT Executive. Not included in these sections of Pascal code are: the global executive, five way voting, clock synchronization, interactive consistency, low level broadcasting, and program loading, initialization, and schedule construction.

Source record↗

2008 NASA Range Safety Annual Report

Welcome to the 2008 edition of the NASA Range Safety Annual Report. Funded by NASA Headquarters, this report provides a NASA Range Safety overview for current and potential range users. This year, along with full length articles concerning various subject areas, we have provided updates to standard subjects with links back to the 2007 original article. Additionally, we present summaries from the various NASA Range Safety Program activities that took place throughout the year, as well as information on several special projects that may have a profound impact on the way we will do business in the future. The sections include a program overview and 2008 highlights of Range Safety Training; Range Safety Policy; Independent Assessments and Common Risk Analysis Tools Development; Support to Program Operations at all ranges conducting NASA launch operations; a continuing overview of emerging Range Safety-related technologies; Special Interests Items that include recent changes in the ELV Payload Safety Program and the VAS explosive siting study; and status reports from all of the NASA Centers that have Range Safety responsibilities. As is the case each year, contributors to this report are too numerous to mention, but we thank individuals from the NASA Centers, the Department of Defense, and civilian organizations for their contributions. We have made a great effort to include the most current information available. We recommend that this report be used only for guidance and that the validity and accuracy of all articles be verified for updates. This is the third year we have utilized this web-based format for the annual report. We continually receive positive feedback on the web-based edition, and we hope you enjoy this year's product as well. It has been a very busy and productive year on many fronts as you will note as you review this report. Thank you to everyone who contributed to make this year a successful one, and I look forward to working with all of you in the years to come.

Lamoreaux, Richard W.↗

Merits of flywheels for spacecraft energy storage

Flywheel energy storage systems which have a very good potential for use in spacecraft are discussed. This system can be superior to alkaline secondary batteries and regenerable fuel cells in most of the areas that are important in spacecraft applications. Of special importance, relative to batteries, are lighter weight, longer cycle and operating life, and high efficiency which minimizes solar array size and the amount of orbital makeup fuel required. Flywheel systems have a long shelf life, give a precise state of charge indication, have modest thermal control needs, are capable of multiple discharges per orbit, have simple ground handling needs, and have characteristics which would be useful for military applications. The major disadvantages of flywheel energy storage systems are that: power is not available during the launch phase without special provisions; and in flight failure of units may force shutdown of good counter rotating units, amplifying the effects of failure and limiting power distribution system options; no inherent emergency power capability unless specifically designed for, and a high level of complexity compared with batteries. The potential advantages of the flywheel energy storage system far outweigh the disadvantages.

Gross, S.↗

Methods for Determining Blood Flow Through Intact Vessels of Experimental Animals Under Conditions of Gravitational Stress and in Extraterrestrial Space Capsules

Work during the initial six months of this program has proceeded along three lines: (1) technical development of blood flowmeter instrumentation: (2) surgical considerations related to special problems of chronic implantation of flowmeter probes: (3) study of the relationship between levels of blood flow and organ activity. Principal engineering effort has been focused on the fundamental phenomena operative in the flowmeter probe and on probe design. Two probes have been constructed and a third is nearing completion. A previously unrecognized source of zero drift has been discovered and corrected. has been designed, assembled, tested and successfully employed in work on the several probes. A significant innovation which has been introduced is the use of a transformer coupled input for suppression of unwanted common mode signals. New low noise transistor amplifiers with characteristics suitable for space vehicle packaging are being developed. Linearity of the present apparatus has been found to extend at least into the near turbulent flow region. Attention has been directed to the two vascular beds of physiologic interest that present particular problems with regard to chronic implantation of flowmeter probes, the myocardium and the liver. Surgical techniques have been perfected that will permit myocardial and liver blood flow measurement. Two groups of animals have successfully undergone surgery and await the implantation of probes. Studies of the relationship between organ blood flow and levels of physiologic activity have been initiated. The first organ system studied was the heart, For the first time autoregulatory mechanisms have been demonstrated within the myocardial vascular bed which rapidly and precisely maintain coronary blood flow at a level i n keeping with the magnitude of cardiac work, Following a summary statement of the status of the program, the work performed is described, A financial review of expenditures incurred and a proposal for future funding are appended,

Shaw, R. F.↗

Algebraically special space-time in relativity, black holes, and pulsar models

The entire field of astronomy is in very rapid flux, and at the center of interest are problems relating to the very dense, rotating, neutron stars observed as pulsars. the hypothesized collapsed remains of stars known as black holes, and quasars. Degenerate metric form, or Kerr-Schild metric form, was used to study several problems related to intense gravitational fields.

Adler, R. J.↗

Dynamic stall: An example of strong interaction between viscous and inviscid flows

A study was done of the phenomena concerning profiles in dynamic stall configuration, and more specially those related to pitch oscillations. The most characteristic experimental results on flow separations with a vortex character, and their repercussions on local pressures and total forces were analyzed. Some aspects of the methods for predicting flows with the presence (or not) of boundary layer separation are examined, as well as the main simplified methods available to date for the calculation of total forces in such configurations.

Philippe, J. J.↗

Potential applications of advanced aircraft in developing countries

An investigation sponsored by NASA indicates that air transportation can play an important role in the economic progress of developing countries. By the turn of the century, the rapid economic growth now occurring in many developing countries should result in a major redistribution of the world's income. Some countries now classified as 'developing' will become 'developed' and are likely to become far more important to the world's civil aviation industry. Developing countries will be increasingly important buyers of conventional subsonic long-haul jet passenger aircraft but not to the point of significant influence on the design or technological content of future aircraft of this type. However, the technological content of more specialized aircraft may be influenced by developing country requirements and reflected in designs which fill a need concerning specialized missions, related to short-haul, low-density, rough runways, and natural resource development.

Maddalon, D. V.↗

Determination of the properties of magnetic turbulence in radio sources

The transport of polarized synchrotron radiation in a source possessing a highly irregular magnetic field, as proposed by Laing has been considered. The transport equation has been solved in a special case, relating the observable correlation functions in the Stokes parameters Q and U to the correlation functions of magnetic field and plasma density in the source. A rough application of the results to observations of the radio galaxy 3C 166 indicates that the turbulent scale length may be a few percent of the lobe size.

Spangler, S. R.↗

Study of flywheel energy storage for space stations

The potential of flywheel systems for space stations using the Space Operations Center (SOC) as a point of reference is discussed. Comparisons with batteries and regenerative fuel cells are made. In the flywheel energy storage concept, energy is stored in the form of rotational kinetic energy using a spinning wheel. Energy is extracted from the flywheel using an attached electrical generator; energy is provided to spin the flywheel by a motor, which operates during sunlight using solar array power. The motor and the generator may or may not be the same device. Flywheel energy storage systems have a very good potential for use in space stations. This system can be superior to alkaline secondary batteries and regenerable fuel cells in most of the areas that are important in spacecraft applications. Of special impotance relative to batteries, are high energy density (lighter weight), longer cycle and operating life, and high efficiency which minimizes the amount of orbital makeup fuel required. In addition, flywheel systems have a long shelf life, give a precise state of charge indication, have modest thermal control needs, are capable of multiple discharges per orbit, have simple ground handling needs, and have the potential for very high discharge rate. Major disadvantages are noted.

Gross, S.↗

Use of Space Station for Earth and Planetary Exploration

The Earth and Planetary Exploration program attempts to develop an understanding of the earth as a planet by utilizing the capability of instruments in space to explore the earth. Studies of the solar system are conducted to gain an understanding of its origin and evolution. The facilities for planetary observations will be greatly extended by making use of a Space Station. Special demands related to the appropriate utilization of a Space Station observatory are discussed, taking into account the employment of ultraviolet spectroscopy for the study of planetary atmospheres and comets, advantages provided by infrared spectroscopy, far-infrared and submillimeter spectroscopy and radiometery, and the search for other planetary systems. The capabilities provided by the Space Station for an investigation of earth resources are explored. Attention is given to vegetation research and observations, land cover dynamics, hydrologic cycle research, geological research, suitable instruments, and a study of crustal dynamics.

Piotrowski, W. L.↗