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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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Work accomplished by the Jet Propulsion Laboratory (JPL) under contract to NASA in 1985 is described. The work took place in the areas of flight projects, space science, geodynamics, materials science, advanced technology, defense and civil programs, telecommunications systems, and institutional activities.
Following a brief history of the NACA investigation of jet propulsion, a discussion is given of the general investigation and analysis leading to the construction of the jet-propulsion ground-test mock-up. The results of burning experiments and of test measurements designed to allow quantitative flight performance predictions of the system are presented and correlated with calculations. These calculations are then used to determine the performance of the system on the ground and in the air at various speeds and altitudes under various burning conditions. The application of the system to an experimental airplane is described and some performance predictions for this airplane are made.
Following a brief history of the NACA investigation of jet propulsion, a discussion is given of the general investigation and analysis leading to the construction of the jet-propulsion ground-test mock-up. The results of burning experiments and of test measurements designed to allow quantitative flight performance predictions of the system are presented and correlated with calculations. These calculations are then used to determine the performance of the system on the ground and in the air at various speeds and altitudes under various burning conditions. The application of the system to an experimental airplane is described and some performance predictions for this airplane are made.
An investigation of a heated jet was conducted in conjunction with tests of an axial-flow jet-propulsion engine in the Cleveland altitude wind tunnel. Pressure and temperature surveys were made across the jet 10 and 15 feet behind the jet-nozzle outlet of the engine. Surveys were obtained at pressure altitudes of 10,000, 20,000, 30,000, and 40,000 feet with test-section velocities from 30 to 110 feet per second and test-section temperatures from 60 F to -50 F. From measurements taken throughout the operable range of engine speeds, tail-pipe outlet temperatures from 500 F to 1250 F and jet velocities from 400 to 2200 feet per second were obtained. The jet-survey data presented extend the work previously done with low-velocity and low-temperature jets to the region of high velocities and high temperatures. The results obtained agree with previously determined experimental data and with predicted theoretical expressions for the dimensionless transverse velocity and temperature profiles across a jet. The spread of both the temperature and the velocity profiles was very nearly linear. Dimensionless plots of temperature and velocity along the axis of a heated jet agree with experimental results of tests with a cold jet.
This series of tests was undertaken to determine how much the reaction thrust of a jet could be increased by the use of thrust augmenters and thus to give some indication as to the feasibility of jet propulsion for airplanes. The tests were made during the first part of 1927 at the Langley Memorial Aeronautical Laboratory. A compressed air jet was used in connection with a series of annular guides surrounding the jet to act as thrust augmenters. The results show that, although it is possible to increase the thrust of a jet, the increase is not large enough to affect greatly the status of the problem of the application of jet propulsion to airplanes.
Projects of the Jet Propulsion Laboratory leading to and including development of the Sargent guided missiles are discussed.
The historical development of the Jet Propulsion Laboratory (JPL) of generic computer programs for solving the H-M-H equations of motion of point-connected sets of rigid bodies in a topological tree is traced, as well as the application of these programs and the multibody modelling approach to the design of spacecraft control systems. These include thrust vector control and science instrument articulation on such vehicles as Mariner 9, Mariner 10, Viking Orbiter, and Voyager.
Pressure losses through the combustion chamber and the combustion efficiency of the 19B-2 and 19B-8 jet-propulsion engines and the combustion efficiency of the 19XB-1 jet-propulsion engine are presented.Data were obtained from an investigation of the complete engine in the NACA Cleveland altitude wind tunnel over a range of simulated altitudes from 5000 to 30,000 feet and tunnel Mach numbers from less than 0.100 to 0.455. The combustion-chamber pressure loss due to friction was higher for the 19B-2 combustion chamber than for the 19B-8. The 19B-2 combustion chamber had a screen of 40-percent open area interposed between the compressor outlet and the combustion-chamber inlet. The screen for the 19B-8 combustion chamber had a 60-percent open area, which except for a small difference in tail-pipe-nozzle outlet area represents the only point of difference between the standard 19B-2 and 19B-8 combustion chambers. The pressure loss due to heat addition to the flowing gases in the combustion chamber was approximately the same for the 19B-2 and 19B-8 configurations. Altitude and tunnel Mach number had no significant effect on the over-all total-pressure loss through the combustion chamber. A decrease in tail-pipe-nozzle outlet area (tail cone out) resulted in a decrease in combustion-chamber total-pressure loss at high engine speeds.
Early history of Russian jet propulsion study group
Cumulative index of Jet Propulsion Laboratory bibliographies
A flight investigation of an I-16 jet propulsion engine installed in the waist compartment of a B-24M airplane was made to determine the effect of induction-system icing on the performance of the engine. Flights were made at inlet-air temperatures of 15 deg, 20 deg., and 25 F, an indicated airspeed of 180 miles per hour, jet-engine speeds of 13,000 and 15,000 rpm, liquid-water contents of approximately 0.3 to 0.5 gram per cubic meter, and an average water droplet size of approximately 50 microns. Under the most severe icing conditions obtained, ice formed on the screen over the front inlet to the compressor and obstructed about 70 percent of the front-inlet area. The thrust was thereby reduced 13.5 percent, the specific fuel consumption increased 17 percent, and the tail-pipe temperature increased 82 F. No icing of the rear compressor-inlet screen was encountered.
Bibliography on Jet Propulsion Laboratory technical reports and memorandums, space programs summary, astronautics information, and literature searches
2009 was truly the year of astronomy at the Jet Propulsion Laboratory. While the world at large was celebrating the International Year of Astronomy, we were sending more telescopes into space than in any other year, ever. As these missions unfold, the astronomers are sure to change the way we see the universe. One of the newly lofted observatories is on a quest to find planets like our own Earth orbiting other stars. Another is a telescope that gathers infrared light to help discover objects ranging from near-Earth asteroids to galaxies in the deepest universe. We also contributed critical enabling technologies to yet two other telescopes sent into space by our partners in Europe. And astronauts returned to Earth with a JPL-built camera that had captured the Hubble Space Telescope's most memorable pictures over many years. And while it was an epic time for these missions, we were no less busy in our other research specialties. Earth's moon drew much attention from our scientists and engineers, with two JPL instruments riding on lunar orbiters; previously unseen views of shadowed craters were provided by radar imaging conducted with the giant dish antennas of the Deep Space Network, our worldwide communication portal to spacecraft around the solar system. At Mars, our rovers and orbiters were highly productive, as were missions targeting Saturn, comets and the asteroid belt. Here at our home planet, satellites and instruments continued to serve up important information on global climate change. But our main business is, of course, exploring. Many initiatives will keep us busy for years. In 2009, NASA gave approval to start planning a major flagship mission to Jupiter's moon Europa in search of conditions that could host life, working with our partners in Europe. In addition to our prospective Earth science projects, we have full slates of missions in Mars exploration, planetary exploration and space-based astronomy. This year's annual report continues our recent direction of recounting the Laboratory's accomplishments throughout the year month by month.
A study was made of the performance of a jet-propulsion system composed of an engine-driven blower, a combustion chamber, and a discharge nozzle. A simplified analysis is made of this system for the purpose of showing in concise form the effect of the important design variables and operating conditions on jet thrust, thrust horsepower, and fuel consumption. Curves are presented that permit a rapid evaluation of the performance of this system for a range of operating conditions. The performance for an illustrative case of a power plant of the type under consideration id discussed in detail. It is shown that for a given airplane velocity the jet thrust horsepower depends mainly on the blower power and the amount of fuel burned in the jet; the higher the thrust horsepower is for a given blower power, the higher the fuel consumption per thrust horsepower. Within limits the amount of air pumped has only a secondary effect on the thrust horsepower and efficiency. A lower limit on air flow for a given fuel flow occurs where the combustion-chamber temperature becomes excessive on the basis of the strength of the structure. As the air-flow rate is increased, an upper limit is reached where, for a given blower power, fuel-flow rate, and combustion-chamber size, further increase in air flow causes a decrease in power and efficiency. This decrease in power is caused by excessive velocity through the combustion chamber, attended by an excessive pressure drop caused by momentum changes occurring during combustion.
Energy transfer mechanisms in radiation, water, and regeneratively cooled, and MPD arc jet propulsion devices
The lunar-probe tracking program at the Jet Propulsion Laboratory has two prime objectives: (1) provide real-time predictions of the direction of the probe from various observation stations; (2) establish a reliable trajectory corresponding to the actual flight path of the probe. The tracking program, although developed for use with lunar probes, can be used for interplanetary probes if certain modifications are made. The program, as developed for the IBM 704 digital computer, has two distinct phases. First, the equations of motion and the variational equations are integrated to each observation time where the elements of the equation A (sub u) equals b [linearization of the maximum likelihood equations] are computed. The second phase is concerned with the solution of a specified subset of A (sub u) equals b. Flexibility and ease of operation have been major objectives in writing the 704 program. The number of data points and tracking stations that may be used is limited only by computing time and core storage. Input formats and operating instructions are presented for utilizing the various computational options available in the program.
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