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An organic Rankine Bottoming cycle added to Diesel engines used for long-haul trucks has the potential of improving their peak fuel economy by up to 15% over a typical duty cycle. General Electric has developed a multi-vane rotary expander which has a measured isentropic brake efficiency of 80+% over a wide range of speed and power levels with organic working fluids. High cycle efficiency for design and off-design conditions is achieved with the multi-vane expander. The potential advantages of the multi-vane expander for the Diesel engine bottoming cycle include the elimination of a high speed gear box and the potential for over 80% isentropic engine efficiency. The multi-vane expander is a ruggedly built component running at Diesel engine speed. This paper describes the design and evaluation of a nominal 40 HP multi-vane expander for this application.

Previous studies had demonstrated the economic and technical feasibility of producing high-quality forgings for aircraft turbine engine parts from hot-isostatically pressed (HIP) Rene 95 powder billets. The present program was aimed at developing a production practice for making HIP + forged turbine discs. The major goal was improved product fabricability and reliability with minimum cost. The program was conducted using argon atomized Rene 95 powder. Experimental studies were conducted to evaluate the effect of powder characteristics, HIP parameters, preform design, and forging conditions on forgeability, microstructure, and mechanical properties. The results of these studies were incorporated into a pilot production run in which 10 disc forgings were made and evaluated. The selected process involved the consolidation of -60 mesh powder to full density by hot-isostatic pressing at a temperature above the γ' solvus temperature.

The work reported in this paper has been conducted by a team from GE-Aircraft Engines, GE-CR&D, and Sundstrand under a contract sponsored by the USAF, Wright Laboratories, WPAFB, Contract No. F33615-90-C-2052. The objective of this contract is to prove the feasibility of an Integral Starter/Generator (IS/G) through the preliminary design stage and demonstrate the starter/ generator technology in the externally mounted version utilizing switched reluctance machine technology. This paper will report on the progress for the EIS/G-system through the initial testing stage. Comparison of the finished hardware with the design results presented earlier will lead of the paper. This is followed by the discussion of the early testing results for the system testing. Recommendation on additional testing will be presented at the end of the paper.

Measurement of dimensional characteristics of airfoil parts is primarily a manual, labor intensive operation. It employs a wide variety of gages that vary from very expensive optical comparitors to inexpensive pin gages. An automatic non-contacting inspection gage capable of measuring most dimensional characteristics would be cost effective, simplify inspection operations, consolidate a number of gages into one, and improve overall inspection reliability by minimizing human involvement. This paper presents the results of the design and development of a demonstrator semi-automatic laser gage dimensional inspection system that addresses this problem.

A new silicone rubber formed-in-place gasketing concept has been developed which has greatly reduced the incidence of warranty oil leaks in engine and drive train components. This concept utilizes a combination of joint configuration and unique cured properties of the silicone formed-in-place gasketing material to achieve leak-free performance over the life of the component.

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.

Reliability can be improved by the careful definition of the mechanical properties of engineering materials. Methods to define these properties for design functions by the use of statistics and probability concepts are presented. In addition, methods will be presented for quantitatively measuring the effects of specification screening on the improved properties of the acceptable materials. By selection of the proper design allowables based on required failure rate, reliability can be designed into components using the techniques discussed and illustrated.

To facilitate the development of the Space Reactor Power System (SRPS) controller, a rapid prototyping and multi-phased development methodology is being utilized. The rapid prototyping environment used in the development models both the controller and the system being controlled. Since the validation of the SRPS control strategies is a long lead activity to ensure the required safety and control features, the SRPS controller development is carried out in phases, starting with normal modes of operation and followed by transient and off-normal modes. In every phase, the rapid prototyping of the control strategies is used (1) to establish well-defined controller requirements, (2) to perform fast identification of changes and refinement of the strategies, and (3) to conduct in-phase correction and optimization of the strategy and component development.

The term “SP-100” is synonymous with a set of technologies that can be utilized to provide long lifetime, reliable, safe space power over the range of kilowatts to megawatts [1] using a nuclear reactor as the heat source. This paper describes recent development progress in a number of technology areas such as fuel, materials, reactivity control mechanisms and sensors. Without exception, excellent technical progress is being accomplished in all areas under development to optimize spacecraft performance characteristics.

The SP-100 Space Reactor Power System is being developed by GE, under contract to the U.S. Department of Energy, to provide electrical power in the range of 10's to 100's of kW. The system represents an enabling technology for a wide variety of earth orbital and interplanetary science missions, nuclear electric propulsion (NEP) stages, and lunar/Mars surface power for the Space Exploration Initiative (SEI). An effective infrastructure of Industry, National Laboratories and Government agencies has made substantial progress since the 1988 System Design Review. Hardware development and testing has progressed to the point of resolving all key technical feasibility issues. The technology and design is now at a state of readiness to support the definition of early flight demonstration missions. Of particular importance is that SP-100 meets the demanding U.S. safety, performance, reliability and life requirements.

System level design studies of space applications ranging in power from 77 kWt to 200 MWt have indicated no practical limit to the thermal power that can be reliably generated by a space reactor system based on the technologies being developed in the SP-100 program. These technologies include uranium nitride fuel, PWC-11/rhenium bonded fuel cladding, PWC-11 structural material for the lithium coolant boundary, electromagnetic coolant pumps, safety and reactivity control drive mechanisms, sensors, shielding materials, etc. at operating temperatures up to 1400K. The physical arrangements and characteristics of the nuclear reactor materials are described. The physical size of components and the arrangement of components change, but the basic technologies required are generally the same, irrespective of the total power output.

Researchers now have the means to evolve complex manned and unmanned space missions using all of their complex support systems in a fully adaptive visual environment. The expected interactive nature of space missions requires powerful, flexible and comprehensive simulation hardware and software to develop and verify concepts, systems, and procedures. Correlation of visual, sensor, and radar imagery is essential due to new sensor blending and fusion techniques that characterize complex systems and missions. Only through total visual, non-visual and mission environment simulation, combined with analytical tools, can reliable systems and missions be developed. The same can be said of the simulation-based training programs that must be developed for ground and flight mission crews. If maximum situational awareness cannot be trained through simulation, it may be too risky, too expensive or even too late to acquire during a mission.