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Solar electric spacecraft for interplanetary missions including asteroid belt survey, Jupiter flyby and out-of-elliptic survey

The current state of a research program to study flows in radial turbomachines at both on- and off-design conditions is described. Numerical solutions of the flow within a rotating impeller are described based on potential theory using a direct method of solution instead of by relaxation. The experimental apparatus comprising a rotating cascade rig is described. The rig consisted essentially of a rotor mounted horizontally in an open circular water tank. An external pipe system enabled the water to be circulated for either radial inflow or radial outflow. The rotor speed could be varied up to 300 rpm. A variety of perspex shrouded rotor geometries up to a maximum diameter of 3 ft 6 in could be tested. Flow visualization by means of polystyrene particles could be observed by a camera mounted above the rotor on its axis and driven at the same angular speed. A 12-channel electronic flash unit enabled the particle velocity and directions to be photographed. As an alternative to the flow visualization system, a bank of manometers, could be mounted above the rotor and driven at the same rotational speed, i.e., with no relative movement. Static pressure measurements could be taken on the blade faces and within the rotor passages. A comparison is made of the experimental and analytical results obtained for one straight vaned, constant area rotor.Copyright © 1971 by ASME

The characteristics of defects exhibiting fringe contrast in GaAs annealed after implantation with Be have been examined using weak-beam dark-field transmission electron microscopy. Semi-insulating, chromium-doped, [001] GaAs wafers were implanted with 35 keV Be ions to a fluence of 1 x 1015 ions/cm2.

Legionella gormanii, previously isolated only from the environment, was grown from the bronchial brush specimen of a patient with pneumonia. The organism was characterized by serologic, biochemical, and DNA hybridization studies.

A Legionella-like organism (strain 82A3105; ATCC 43736) was isolated from a lung aspirate taken from a patient with pneumonia. Results of physiologic, gas-liquid chromatographic, genetic, and serologic tests showed that strain 82A3105 and four additional clinical isolates belong to a new Legionella pneumophila serogroup, serogroup 13.

A multifunction circuit is described that protects instruments connected or coupled to a superconducting magnet in the event of a quench.

The Farnboro Indicator gives a large permanent pressure-time diagram with a linear time base and pressure scale. In its latest versions accurate diagrams can be taken over a wide pressure range. The major disadvantage is that it can only be used for cyclic repetitive processes such as those occurring in engines or specially designed machines. During the course of an investigation of pressure wave phenomena in an exhaust pipe of a high-pressure-charged two-stroke cycle engine model the Farnboro indicator was used to record shock waves travelling along the pipe and to measure the total head pressure downstream of a nozzle placed at the end of the pipe and hence to calculate the transient velocity. In this note some of the pressure records taken in the investigation are presented.

The facilities for the measurement of sound propagation from air to ground for altitudes up to 5000 feet and for distances up to two miles will be described. Propagation has been studied for various angles from 15 to 90 degrees with the earth's surface. In addition to the measurement of sound, various measures of atmospheric meteorological conditions are obtained. The sound source is a Consolidated Vultee B‐13 airplane which is flown in prescribed patterns above the recording installation. Instrumentation for recording and analyzing data will be described and illustrations of specific flight data will be presented. Results of this study will be presented in the following paper. [This research was supported by U. S. Air Force Contract AF33(616)‐2470.]