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Results for “Exploratory Study”

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

Exploratory study of friction welds in Udimet 700 and TD-Nickel bar

Friction welded butt joints were made in both Udimet 700 and TD-Nickel bar. Also, dissimilar metal friction welds were made between these materials. Friction welding of Udimet 700 shows great promise because the welds were found to be as strong as the parent metal in stress rupture and tensile tests at 760 and 980 C. The weld line was not detectable metallographically in the heat treated condition. Friction welding for TD-Nickel, however, holds little if any promise. TD-Nickel friction weldments could support only 9 percent as much stress as the base metal for a 10-hour stress-rupture life at 1090 C. Dissimilar Udimet 700/TD-Nickel friction welds could sustain only 15 percent as much stress as the TD-Nickel parent metal for a 10-hour rupture life at 930 C.

Moore, T. J.↗

Exploratory study of the effects of injection configurations and inlet flow conditions on the characteristics of flow in spherical chambers

Flow visualization studies were conducted to evaluate techniques for injecting simulated-fuel and simulated-propellant gases into a spherical cavity for application to open-cycle gaseous-core nuclear rockets. Preliminary studies were conducted with six simulated-fuel injectors and eight simulated-propellant injection configurations. Additional tests were conducted with the best configuration to determine the effect of weight-flow ratio, gas density ratio, injector location, and flow distribution on the simulated-fuel containment characteristics.

Johnson, B. V.↗

Top management and management science: An exploratory study in 15 Federal civilian agencies

A study of the relation between top managers in Federal agencies and the operations research and management science (OR/MS) group is reported. Sixteen managers were questioned about the following characteristics: closeness of top managers to OR/MS groups; top managers' attitudes toward the OR/MS activities; relation between closeness and these attitudes; and top managers' use of OR/MS groups. It is concluded that OR/MS is relevant to many top managers and that OR/MS has begun to play a role in decisions. Top management attitudes and actions are not related in obvious ways. The consequences to top management's use of and closeness to an OR/MS group need not be the success of the group as a professional, innovative, research-oriented unit.

White, M. J.↗