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Initial preliminary development phases of two distinct SP-100 control drive assembly bearing test programs were successfully completed at elevated temperature in vacuum. The first was for the reflector drive line spherical self-aligning bearings. Each bearing consisted of a carbon-graphite ball mounted on an aluminum oxide-coated Ta-10%W shaft, captured by an aluminum oxide-coated Ta-10%W socket. One set of these bearings was exposed to temperatures up to 1180K (1665°F) at 1.33x10-6 Pa (1x10-8 torr) and subjected to 38000 cycles of motion. Friction coefficients were found to be between 0.11 and 0.25 over the full range of operation. Overall performance of the bearings was excellent, with only slight wear observed. The second test program was for the safety rod slider bearing. Zirconium carbide coated Nb-1%Zr bearing pads were stroked inside a molybdenum tube at temperatures up to 1422K (2100°F) at ∼1.33x10-6 Pa with a normal load of 1.02 Kg between each sliding surface.

The SP-100 reactor will operate at temperatures up to 1500K in high vacuum. Development of bearing coatings is necessary to avoid self welding and/or galling of moving components. No experience base exists for these conditions-the early SNAP (Space Nuclear Auxiliary Power) program requirements were over 400K lower with shorter lifetime requirements. To address the SP-100 needs, a tribology development program has been established at GE to investigate candidate coating materials. Materials were selected based on their high thermodynamic stability, high melting point, compatibility with the substrate, and coefficients of thermal expansion similar to niobium-1% zirconium - the candidate structural material for SP-100. An additional requirement was that the deposition processes should be commercially available to coat large components.

Recent Generic Flight System (GFS) updates have necessitated revisions in the initial startup and restart control strategies. The design changes that have had the most impact on the control strategies are the addition of the Auxiliary Cooling and Thaw (ACT) system for preheating the lithium filled components, changes in the reactivity worths of the reflectors and safety-rods such that initial cold criticality is achieved with only a small amount of reflector movement following the withdrawal of the safety-rods, and the removal of the scram function from the reflectors. Revised control and operating strategies have been developed and tested using the SP-100 dynamic simulation model, ARIES-GFS. The change in the total reactivity worths of the reflectors and safety-rods has eliminated the need for the use of fast and slow reflector drive speeds during the initial on-orbit approach to criticality.

As part of the SP-100 Space Reactor Power System Program being undertaken for the U. S. Department of Energy, GE is developing a thermoelectric (T/E) power converter which utilizes reactor delivered heat and transforms it into usable electric power by purely static means. This converter is based to GE's product line of successful thermoelectric space power systems. The SP-100 power converter embodies the next generation improvement over the type of T/E converter successfully flown on the six U. S. space missions. That is, conduction coupling of T/E cell to both the heat source and the heat rejection elements. The current technology utilizes radiation coupling in these areas. The conduction coupling technique offers significant improvements in system specific power since it avoids the losses associated with parasitic ΔT's across the radiation gap between the heat source and the hot junction of the thermoelectric (T/E) cell.

The approach that was utilized to start up and requalify manufacture of the thermoelectric unicouple devices for the Cassini RTG (Radioisotope Thermoelectric Generator) program are described in this paper. Key elements involved in this effort were: engineering review of specifications; training of operators; manufacturing product verification runs; and management review of results. Appropriately, issues involved in activating a fabrication process that has been idle for nearly a decade, such as upgrading equipment, adhering to updated environmental, health, and safety requirements, or approving new vendors, are also addressed. The cumulative results of the startup activities have verified that a production line for this type of device can be reopened successfully.

An acceleration of metal replacement to reinforce thermoplastic composites is positioned to impact the transportation markets through a joint venture between PPG Industries and GE Plastics, called AZDEL, Inc. The strength of both companies' strong technological base in glass and engineering thermoplastic resins is the key. The resulting long continuous glass thermoplastic composites have high strength to weight ratios, provide tough durable products, facilitate combining functions in design, and because of its high speed manufacturing processes, is cost effective. In addition, these materials can be post fabricated during the assembly phase, easily repaired and conveniently recycled. Value added secondary operations for both the captive or custom molders provide another avenue for cost reductions.

Alternative engine concepts to the advanced high bypass turbofan which have promise of reducing energy consumption including regenerative cycles and other engines with heat exchangers, unconventional engine arrangements such as geared fan engines, and high disc loading turboprops. After initial screening, several concepts were selected for a systematic evaluation of the merits of each relative to a high bypass turbofan based on advanced technology consistent with the mid 1980's time period. Both mission fuel and direct operating cost for typical long range transport missions were considered in the evaluation.

Aircraft starting and generating systems heretofore have been largely the result of joining together available components. Recent studies have demonstrated that substantial benefits in weight, cost, size, and performance may be realized through a total system approach. This paper identifies the types of information required, and the methods of system analysis employed, to design an optimized system.

The major technological developments which have made possible the trend towards higher temperatures in modern aircraft gas turbine engines are discussed. The relative importance of manufacturing processes, material developments, cooling techniques, analytical design procedures, rupture and cyclic life considerations, and aerodynamic and mechanical design improvements are discussed along with illustrative examples and technical data. The need for a balanced design approach is stressed, and examples are given where trade-offs can be made. It is noted that the advances in aircraft engines during the last 10 years have been based on the evolution of sound engineering principles, extensive component and engine development, and careful consideration of the operational requirements rather than a tremendous breakthrough or revolutionary concept in any one area.

A four-legged, 3000 lb, walking truck test bed has been developed and the test results have proved the feasibility of walking machines. Effectiveness of this control method where the machine mimics man’s arm and leg movements was shown by a variety of maneuverability experiments. Therefore, it has been proved that it is possible to develop this vehicle concept, and the control method involved, to effectively emulate animals in the way they travel on rough terrain. Human perception, judgment, and agility are transmitted through the machine in a manner that lets the operator easily imagine that the machine is merely an effective extension of his own appendages. The human psychomotor action, coupled with the power and ruggedness of the machine, provides a valuable marriage. It opens new vistas not only for rough terrain vehicles but also for a variety of other manipulative machines. Many jobs require the sensing acuity of man but are too tough for the frail human flesh.

THE problem of this study was: 1. Can a method of analysis be found which adequately predicts the heat-transfer and cyl-wall temperature phenomena in diesel engines? 2. Are there criteria for the design of diesel engine cyl that give the limits of reliable practice as found in typical diesels? Such a method of analysis is detailed in this paper. Design criteria were also found which appear applicable to broad classes of diesel engines. It was determined that the method was useful in prediction of the thermodynamic performance of a diesel insofar as the influence of cyl heat transfer on efficiency, power, and cooling load were predictable.