31,969 research outputs found
Combined actuator and latch for cartridge powered actuator
Combined attenuator and latch stops and latches in place a given mass which is to be moved a discrete distance to effect a desired condition. This device is used in a retraction actuator driven by a pyrotechnic thruster, and can be tailored to meet specific design requirements
Pressure limiting propellant actuating system
A pressure limiting propellant activating system for simultaneously limiting the output force while maintaining a constant output pressure from the combustion chamber is described. The propellant actuated system includes an outer barrel, outer housing and a combustion chamber. A main piston is movable in the barrel housing when gas pressure is developed in the combustion chamber. A relief piston is concentrically mounted and fixedly movable with the main piston when gas pressure is exerted from the combustion. A relief piston has a force-activated separation mechanism for limiting the output force while simultaneously maintaining constant output pressure on the main piston from the combustion chamber
Polarized Scattering in the Vicinty of Galaxies
Some bright cD galaxies in cluster cooling flows have Thomson optical depths
exceeding 0.01. A few percent of their luminosity is scattered and appears as
diffuse polarized emission. We calculate the scattering process for different
geometric combinations of luminosity sources and scattering media. We apply our
results to galaxies, with and without active nuclei, immersed in cooling flows.
We model observations of NGC 1275 and M87 (without active nuclei) in the
presence of sky and galactic background fluxes which hinder the measurement of
the scattered light at optical wavelengths. Current instruments are unable to
detect the scattered light from such objects. However, when a galaxy has an
active nucleus of roughly the same luminosity as the remainder of the galaxy in
V, both the total and polarized scattered intensity should observable on large
scales (5--30kpc), meaning intensity levels greater than 1% of the background
level. For typical AGN and galaxy spectral distributions, the scattering is
most easily detected at short (U) wavelengths. We point out that a number of
such cases will occur. We show that the radiation pattern from the central
nuclear region can be mapped using the scattering. We also show that the
scattered light can be used to measure inhomogeneities in the cooling flow.Comment: 29 pages of TEX, 14 figs, CRSR-1046, in ApJ Nov 20, 199
A computational model for three-dimensional incompressible wall jets with large cross flow
A computational model for the flow field of three dimensional incompressible wall jets prototypic of thrust augmenting ejectors with large cross flow is presented. The formulation employs boundary layer equations in an orthogonal curvilinear coordinate system. Simulation of laminar as well as turbulen wall jets is reported. Quantification of jet spreading, jet growth, nominal separation, and jet shrink effects due to corss flow are discussed
Fundamental remote sensing science research program. Part 1: Scene radiation and atmospheric effects characterization project
Brief articles summarizing the status of research in the scene radiation and atmospheric effect characterization (SRAEC) project are presented. Research conducted within the SRAEC program is focused on the development of empirical characterizations and mathematical process models which relate the electromagnetic energy reflected or emitted from a scene to the biophysical parameters of interest
An evaluation of free-flight test data for aerodynamic heating from laminar, turbulent, and transitional boundary layers. Part II - The X-17 reentry body
Blunt body reentry vehicle aerodynamic heating determinatio
- …