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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 487 records · Page 27

Shallow grooves in journal improve air bearing performance

Bearing designs, which shape the surface to create artificial fluid-film wedges in the absence of any applied radial load, generate radial restoring forces to keep journals from whirling. Helical- or herringbone-grooved journals or rotors show most promise of stable operation, with no sacrifice in load capacity.

Anderson, W. J.↗

Hermetically sealed pump

Mechanically simple, hermetically-sealed pump utilizes pumped fluid for lubrication. The rotor, having helical grooves on the outer surface, functions as both a bearing and pump.

Ludwig, L. P.↗

A positive taper traveling-wave tube

Synchronism can be maintained between the RF beam current and the circuit electromagnetic waves over substantially the entire length of a traveling-wave tube by increasing the pitch of the last portion of the helical wave structure. There is no loss of linearity or beam conversion efficiency.

Grechberg, R. W.↗

Torsional tubular disconnect

Torque driven disconnect maintains connection on a gas supply line until desired parting occurs at a remote location. It consists of a helical plastic tube with a disconnect coupling fitted for an interference condition slip joint, and a rotationally constrained support connected to a gas source.

Curry, K. C.↗

Radio frequency baseband recording technique

Technique uses a helical-scan video recorder with auxiliary signal-conditioning equipment to provide an inexpensive, high-capacity magnetic tape recording of a 112 channel, phase-locked, multiplexed, baseband signal.

Heckman, D. C.↗

Lightweight S-band helix antenna

Pyrotechnically operated S-band helical antenna is developed in which helix is deployed subsequent to antenna placement. Antenna is small, lightweight, and novel in that deployable helix is used in place of fixed dish or horn. It can be designed to cover L- and X-band frequencies.

Cribb, H. E.↗